The following detailed reviews of hurricanes were written by AccuWeather.com Hurricane Expert Joe Bastardi. Bastardi provides daily tropical forecasts, columns, blogs, and videos on our AccuWeather.com Professional website.

• Tropical Storm Bill & Hurricane Claudette
• Tropical Storm Erika
• Tropical Storm Grace
• Tropical Storm Henri
• Hurricane Isabel

BILL AND CLAUDETTE... AN EARLY START TO AN ACTIVE LANDFALL SEASON?
by Joe Bastardi
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It is well worth the time and effort to talk in the same breath about these storms as both of them were seen over 7 days in advance because of pattern recognition techniques; indeed, the idea for a storm like Bill was talked about in many a May discussion and in the hurricane forecast. Neither one had any models forecasting their development more than a few days before.

First, in terms of modelling, the No-Gaps and European were clear-cut winners on Bill. The Canadian had the storm, but during the month of June it had a half dozen storms. So what is to be trusted? Of some value, though, was the fact it was seeing the threat of development as it was perceiving the kind of pattern that could do that. In many ways, the Canadian operational with tropical systems is showing the same bias as the old GFS, then the MRF, previously the AVN, and before that the spectral.

The way they change the name of that is similar to someone trying to hide something.

Reminds me of a scene in "Analyze This" where Billy Crystal is impersonating a mob boss and has 10 different aliases. Sorta like me. When I am not dieting, I am known as Joey Bagadonuts.

But this is not a GFS bash-a-thon. Lest you think it was, the UKMET was hapless until the storm was well developed.

The idea for an early-season storm was a pattern recognition one. As stated several times, the overall pattern this year is one of what I call trof splitting. The first chance was supposed to be mid-June as the pattern flipped from the spring mode of split flow, with the southern branch running east-northeast across the country, to one where amplitude took over. This meant trof amplification and the driving of fronts to the Gulf. Such an occurrence, when combined with the southern end of the trof splitting away, opens up the stage for early development. How so? Well, fronts into Texas stop the normal southeast flow that goes on, so the Gulf becomes a place for low-level convergence. Then what is needed is a tropical wave to arrive on the scene. This adds low level energy, and we have an extra shot of air piling up. Once the trof backs away, ridging develops aloft over top of the large area of convergence. Such a case is one that takes several days. It is complex and must involve the complex simplifying for development. The area must also be "incubated." It is important for the ridge to develop over the systems because if the trof remains open, heat gets carried out and cannot accumulate to warm the atmosphere enough for development in a concentrated area. Last June we saw the same thing, but the trof stayed open enough to allow one attempt after another to be carried northeastward. It poured in Florida, indicative of the mean trof being west, but nothing could organize.

In any case, the needed tropical wave had a low-level center too far south and did not develop in the Gulf, but instead on the Pacific side and out it went. It is interesting to note the SOI was positive at the time.

However, 10-15 days later, the same kind of thing would repeat itself, and this time the wave was farther north and came right up to where the trof split allowed the upper high to develop. The result was Bill.

Bill was not purely tropical at the start, but it used the heat from the tropical wave to develop. It is my theory that what is important here is the relationship of concentrated heat that can build up versus the outside environment around the storm. In other words, the threshold for the core to warm in a colder environment (hybrid) may be lower than in a pure tropical one. It can go ahead and develop, but because the overall conditions are cooler, it may not be capable of reaching the intensity of the deeper tropical systems. So it's the relationship from inside to outside that is important in the development process, not the absolute temperatures. Storms such as the Jan. '92 rouge storm that hit Ocean City, Maryland, with nearly 100-mph winds, a 28.80 pressure and a well-developed eye, are examples of a hybrid warm core system gone to its theoretical max given colder temperatures aloft and at the surface than in summer. The total energy budget is much less, but development to a system with a warmer core than the surrounding area can be quick if conditions are correct.

Karen on Bermuda was like this, and most recently Danny in the north Atlantic this year.

In any case, Bill developed because of the following factors: 1.) the overall pattern, 2.) the lack of wind in the western Gulf because of the front that allowed convergence in the natural southeast flow, 3.) the addition of energy from the Southeast into an already developing system, 4.) the trof split that allowed the upper feature to peel away and let a ridge develop over top of the convergence. Bill developed in a negative NAO.

On the Bastardi Landfall Intensity Scale in our hurricane forecast, Bill received 3 points for zone 2; 2.6 for zone 3; and .5 each for zones 7 and 8 where it went through as a big rainmaker with sub 1010 pressures and gusty winds. Its total score is 6.6, and at 997 mb, it will contribute 3 intensity points to the cumulative intensity reading for the season.

Enter Claudette:

The storm that MADE history was a lesson in how to USE history to forecast. The history? In the last 100 years, no storm that developed in the Caribbean east of 65 west before July 10 (the Caribbean gauntlet, I call it) had made landfall on the United States' coast. The storm's lack in intensification outside of tempting growth spurts all the way to 90 west was normal for deep south latitude origin storms in early and mid-July. This will be examined below as to why. The intensification of a storm hitting the Texas coast from the east is a normal affair for storms that originate east of 92.5 (more than 300 miles of the coast.) That was a key factor in our insistence that this would be a formidable hurricane, probably cat. 2 (I was worried about the upper limit, cat. 3.) It was also why, to avoid some of the nutty things going on with storm classifications today, I use pressure to verify what should happen with a deepening true tropical cyclone. It is interesting to note that Hugo, 24 hours before landfall, was being called a 95 kt storm while its pressure was at 954! The same kind of idea must be applied by TPC, that tightening eyewalls caused by frictional effects of storms coming directly into land will take the storm's wind to the Saffir-Simpson pressure scale. This is not the case for weakening storms, but they must not throw out the lessons touted by some of their previous members (most Bob Case and Gil Clark) in favor of the "new science." It's that simple; here is the rule: Intensifying storms hitting coasts almost within 15 degrees of perpendicular will tighten the eyewall and the wind will go to the pressure. Game, set, match.

First, let examine an "error" on my part. The first was thinking the shear was destroying the storm completely once it was south of Haiti. This was based on past systems that came through there. However, close examination, once the comeback was made and subsequent pulsing of the storm, revealed what the "problem" was. Extend your arm straight and ball up your fist. That was the structure of Claudette; a fist at the end of the arm (the wave.) Most of the storms that come through there, while not strong on the southern side at all, at least had some kind of wind in front of them, and when the low-level circulation shears out, it is strong enough to continue on its own, which is usually death-by-Columbian-heat low (the summertime surface low, most prominent in high shear seasons, that ruins southern and central Caribbean convergence.) In other words, the storms have bundled all the wave energy and the waves are no longer identifiable factors near the storm. Instead, we basically had a tropical wave with a 10-mile wide low pressure on the north side. The wave axis broke out first and left the system behind, which was far enough north not to be caught by the heat low. The convection kept firing in the convergence, and the two managed to stay close enough in maddening tango of "center in, center out" to fight the shear being caused by the climatology of the area, which we will examine below. Within 24 hours of the first attempt at weakening, the fist got under some thunderstorms and briefly exploded to 988, then unwound within a few hours.

What was the cause for all this back and forth, which I described as if it's Apollo Creed and Rocky Balboa slugging it out? Well, first of all, the nighttime increases occurred when pressure rises developed at the end of the diurnal fall time. The theory behind this has to do with pressure reversal allowing for increase in wind speeds in the low to mid levels between areas of subsidence, where pressures are more apt to rise more quickly, and areas of convergence where they are not. The late-night thunderstorms on the Plains are a product of such low-level jets. So "Rocky," who was, in this case, Claudette, would roar back. During the day, though, with heating, the tropical wave, which remained well defined and close by, would distort the storm's circulation, and so we will see it fall apart due to competition. Fooled the first day, I caught on and concentrated on the fact the storm was growing each day. One could not see it in central pressure, but sphere of influence as a larger and stronger inflow pattern was developing on the eastern side and foretold of the storm's potential. This is not hindsighting as it was listed almost every day.

But why the problems at this time of the year over these areas? Well, when faced with the complex, simplify. In the early season, there is an imbalance for tropical development between the cooler oceans and upper levels, and the rapidly warming land. This "feedback" is discussed exhaustively by me in daily posts and in summer forecasting theory. The warming to sustain a true tropical atmosphere takes place over land first. This is why many early-season storms develop close to the coast as the profile of upper warming that can lead to the right stuff temperature-wise is closer to the coast. It is no secret that, overall, the strongest storms occur over oceans closest to land.

As the summer continues and wanes, the land starts to cool. This is the reason that we see the area of most likely landfall shift eastward with time in the late season, so that by October it is very tough, for instance, to get Texas hit. In any case, this imbalance of temperature over the oceans in July, and especially in areas where true tropical systems with much low-level warm air must be able to have a deep tropical atmosphere to sustain their development and accomplish a reversal of the system with height, have to work hard to erase these cold layers. That is what we see. While the synoptic scale outflow level at the top of the storm improved, the layer where the reversal takes place remained stubbornly sheared, as the storm could only do the work needed to get close to the reversal, but not to sustain it. The convective pulses, once exhausted, would collapse and have to start again. But, and this was a big key, the area of inflow and moisture to be lifted was growing each day.

The Yucatan supplies a huge challenge in the early part of the season because it too is a source of daytime convergence and competition, and it tore up the storm. But at night, as it cooled, the center finally was able to organize. Then we were able to draw upon the second part of history for development. The ideas that set the season up in the first place (trof splitting in front of storms) and the history of storms approaching the coast that way.

Before going into that, though, the examination of the second "error," which was the idea the storm would hit near the mouth of the Rio Grande from the initial idea. This was simply going with TPC because it seemed reasonable to me at the time. Contrary to some opinion, (I was once at a hurricane conference on Long Island where one of the conferees got up and said, as a former AccuWeather employee, that we simply disagreed for the sake of disagreement, which is not the case) when in doubt, we do stick with TPC's assessment. However, when doing work on things, if we come up with a different idea, we say so. It's that simple. In the case of the almost open wave Friday, there was doubt where the actual center would develop, and there was worry on my part about a track toward the central Gulf coast if under the cover of darkness Thursday night the center would be pulled even farther eastward. One thing we stated on this site, and on national TV, was that we were confident of the storm's intensity at landfall, and this was in all our press releases...FROM FRIDAY! But while you see me stating opinions contrary to TPC, or calling to task people who seem to talk as if their ideas are the only option, (a quote that their forecast was the best "science" would allow, for instance) this is not done simply to disagree. If one examines the writings over the years, one finds as many compliments as calls for comparison.

The final intensification:

The column discussion on our AccuWeather.com Professional site talked from after the sucker punch that hit me with the shearing incident about the idea this would grow to a formidable hurricane, most likely a cat.2. Indeed, many of the ideas above are just rehash of the column. The Friday before the storm, Lisa Moldovan had consulted with me, much like she does all the time about the Tropics before her regular MSNBC slots in the early morning, and she went on saying there was a strong possibility that this would be a cat. 2 storm at landfall. She also made bold statements well before Bill starting Thursday morning (the storm hit Monday.) This is an example of the teamwork that exists at our company, where people working together over the years play off each other. The point is that Lisa could have just said, "Oh well, that is Bastardi's gig; he'll do it later," but instead, after chit-chatting, she hung herself out to dry. While that is something I am sometimes looked at doing on the web site, it was a great thing for her to do, and it did turn out right.

But why? What did we see? Well, first of all, storms that bust shear zones and turn more to the west usually do intensify. If one notices tracks of many big hurricanes, turns to the west are more than likely indicative of trofs splitting and allowing the hurricane through. This is my tailback and the 8-man front analog, where the shear zone (8-man front) can kill the storm (tackle the tailback), but if it busts through, look out (he...may...go...all... the..way.) In trof splitting, non El Nino or neutral years, the storm contributes heat that tightens the jet in front of the trof. As a piece lifts out, the part of the trof left behind is then driven southwestward by the ridge northwest of the storm. This invites the storm itself to run toward the ridge. This was a big key in tropical classes taught by John Lee at Penn State. As often as not, it's a change of pattern, rather than a steady state pattern, that will set off rapid intensification.

The other, of course, is the coastline itself. Claudette was steadily entraining more low-level warm, humid air into it, and though no pressure falls occurred till Sunday, the notion that the storm was "barely holding on," as I saw coming out of one weather service Sunday morning, was silly. Why? Because it had developed northwest winds to its west, increasing convergence from that side, and the large influx of southeast winds, no longer fighting the Yucatan heat low meant it was no longer a question of if, but how fast, it would intensify. The upper low diving rapidly southwestward through coastal Texas was something discussed in the column on the Tuesday before the storm as the reason Claudette could meander around for a while in the trof split. After doing so, once the upper low backed off, the outflow improved rapidly to its western side. The convection first pulled the center in, which was the first time it wasn't the other way, new convection having to fire over the center, which meant that the hookup had occurred, and contrary to barely hanging on, the storm was on its way. It was a matter of how quickly the "skater" could pull its arms in. In other words, the storm is like a skater and the pulling of the energy in tighter and tighter accelerates the wind to the center. This increases forced convergence and lowers pressures. To a hurricane lover, this is as beautiful as the greatest skater on ice is to someone who loves ice skating. To people in the way, it means trouble.

The call Monday morning on the column was there, but just like with calls on Gustav, Isadore, Lili and Bill, the call was made on national TV before any others were made. When quizzed by Chris Jansen Monday morning, she said to me, "Of course it's too early to say where the storm will go and how strong." I replied, "No, it's not. Matagorda Island, cat. 2, 1-3 p.m. Tuesday." As it was, it was 2 hours to slow, we are seeing resistance to the cat. 2 classification by some, and maybe it was a tad north. The message was there, and it was clear.

The interesting thing is that if the storm had been slower it may have gone to the theoretical limit, which is probably a lower end cat. 3. An intensifying storm hitting the coast at that angle will tighten the eye up and the wind will go to the speed the Saffir-Simpson scale gives. Once again, if we draw on the Bob Case rule, because of the nature of the atmosphere in a situation where a storm is intensifying, it is easier to get the wind down to the surface. The current idea from the Hurricane Center on this baffles me. How many times have strong storms started weakening and the wind went into the tank? Classic examples are Gloria, Floyd, and, of course, the Lili debacle last year. However, if one looks at Celia, Alicia, and Hugo, one sees on the intensification scheme at landfall you get every knot out and perhaps even more. In TPC's own backyard, Andrew did the same thing, on the west path, hitting perpendicular, and years later was labeled a cat. 5. Reliance on recon gives us a good sketch, but the plane can't hit every point at every instant in a storm. It is well worth noting that the Andrew in Louisiana and the Andrew in Florida were two different storms as far as maxing out. The 924 Andrew in Florida was a cat. 5, but the 945 in Louisiana was only borderline cat. 3 with wind. When a storm comes out of an area of max intensification, such as Lili last year, or Andrew, its wind may not live up to its pressure if it's weakening. It is again well worth noting that Hugo had busted a shear zone on its run to the Carolinas, and the wide eye was the sucker punch that did not allow the true max wind of the storm to be realized until it got in where the frictional effects tightened it up. But again, it was deepening to landfall.

Both the storms are history now, and yesterday's glory won't help you today. Interestingly enough, yesterdays' failures can, for the wise will learn from them and make sure they don't happen again. Claudette made history, much like Bertha in 1996 was so unusual for what she did. And if one looks with an objective eye, one can see how by making history, it was past history and the reasons for those things that were as important as anything in the forecasting of the storm.

Claudette receives 7.2 landfall intensity points on the Texas coast, and 1.5 for Louisiana where tropical storm gusts occurred on the southwest coast. This is a total of 8.7; the overall cumulative intensity score was 21 based on difference from 1000mb in lowest pressure (979.) The season, since June 1, stands at 15.3 landfall intensity points. Danny's pressure by the Hurricane Center is disregarded, and I will give it a 995 as its lowest. The intensity score as of 7/20 for the season is 29.

Ciao for now!

ERIKA, THE LAST OF THE WARM-UP STORMS
by Joe Bastardi
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The development of Erica occurred at the end of the part of the season that, to some hurricane forecasters, is referred to as the gravy part of the season, or in other words, before August 15th. Over 75 percent of the destructive part of the hurricane season occurs between August 15th and October 15th. That is not to say that there have not been great storms before. There have. But the coordination of the sea-air interaction due to the lag of the seasons promotes the greatest chance for development and intensification after this part of the season.

Erika was the third of four storms since the opening of the official hurricane season on June 1st to generate a scoreable intensity rating on the Bastardi Scale on the United States coastline. That scale has been developed to try to hone in on the practical aspects of hurricane forecasting...what effect will it have on land masses. The scale is explained in the hurricane forecasts found on the AccuWeather.com Professional site, and is the most advanced attempt at actually quantifying the hurricane season for practical purposes rather than by abstract statements that can not be concretely evaluated. On the scale, Erika scored .5 points for zones 5 and 4, and 2.5 for zone 1 (please refer to the writeup on this.) The score for the season overall stands at 19.5. The intensity rating overall was 13 points for its sub 1000 pressure difference (987 mb.) The score for the season there, which is an objective way of saying what kind of overall season occurred, is 42. This is based on pressures of 997 in Bill, 979 in Claudette, 995 in Danny (not accepting the hurricane center's idea of 1005 mb for a hurricane so long over warm water) and 987 in Erika.

In the Saturday, August 9th, pattern overview and regional highlight tropical section, three areas were looked at for possible development within the next week; the second area being the one that was emphasized as the most likely, and which became Erika. It was stated at the time that we were already starting to inform clients in Florida (actually the Friday before on the Florida Radio network) of a threat there for Thursday and the western Gulf for Saturday. This was some five to seven days beforehand, and some five days before it was officially named.

This identification and forecasts of threats raises the question of exactly what the TPC 5-day forecast for tropical storms and hurricanes is being verified with. It is my opinion that the domain of scoring should be all storms that affect an area, not just ones that develop and hit a day later. In other words, grade based on the end result, not just storms that develop five days away. After all, a tropical storm hitting five days from now has the same effect if it has not developed from five days out as if it has. By eliminating a large part of the domain, one effectively stacks the deck for skill scoring by only using the ones that are obvious. This is something that should be addressed before any boasts are made about the advancement of hurricane forecasting. All storms that hit, not just ones that are developed, must be included. This means, yes, one must be able to predict development. This will eliminate surprise factors. My clients in the northern Gulf once again let me know that some of their associates who do not use our service were surprised at the sudden "development" of Erika. Indeed, as late as 3:30 on Thursday the 14th, only an hour before it was named, cable outlets were talking about it "becoming a depression in a day or two." The point is that just as a case where I may be saying there is a threat a week away based on something does not verify if nothing happens, then if something does happen, but two, three, four, or five days away there is no forecast for it, then that should be included in the domain of skill scoring too. Afterall, are we playing math games to impress ourselves, or are we trying to hone in on the weather for the public, a public that is interested in the end result?

While this may seem critical, if you stand back, it is logical. The typhoon warning center has been doing it for years with their development alerts, and it certainly would continue to up the level of forecasting.

In any case, the system, which was near 25 north and 53 west Saturday the 9th moved steadily westward across the Atlantic. This was yet another in a series of hybrid systems, where an upper low came to the surface, developed the mid- and low-level system, then backed away, allowing an anticyclone to develop over the mid- and low-level systems, which then competed to take over. The process was described each day in our posts.

One big key to the development was a rule first taught to me by my dad and reinforced at work by Dr. Joe Sobel in that size is very important to development of such systems. We knew Claudette would go simply because its sphere of influence increased every day, and the larger the area of warm, moist air that can be tapped, the more the system has a chance to develop. What is important is measuring 24-hour changes and the effects of pulsing. Pulsing occurs when the storm is trying to develop, but unless there is a feedback between the low and mid levels to the upper anticyclone, continued development does not occur. BUT THE SYSTEM GREW LARGER WITH EACH PASSING DAY. In the case of Erika, each pulse got it closer to the time that it could sustain itself as each time the pulse ended and the next one began, it was a little bigger. The non-coordination of the low- and mid-level systems until Thursday afternoon prevented the kind of feedback to sustain the storm. However , by Thursday afternoon, the centers had closed enough that a central convective core developed and the storm was named.

It still took fully 24 hours to get that together, and the storm's rapid westward movement would limit its time over water. We pointed out from Thursday our concern for rapid deepening before landfall (the final 18 hours had a 21 mb pressure drop; 7 in the final hour and a half) based on an almost textbook upper pattern. It is well worth noting that the objective models showed no such occurrence and this was pure forecasting based on nuts and bolts analysis.

The movement south of west and the fast speed, with a landfall one hour outside of the 36-hour window of 6:00-10:00 a.m. and the error of 40 miles did make a difference. The forecasted pressure at landfall was 985, perhaps as low as 965. I really feared the endgame with this, as I cannot remember a storm in the Gulf hitting at 90 degrees to the Texas or Mexico coast that was not deepening. The storm followed a path similar to Barry in 1983, which attained hurricane status with a higher pressure than the 987 measured in Erika. (No, I won't start a rant about this here, so don't worry.) While fear is an emotion, and one should not let such things enter into objective forecasting, the history of such storms made me determined not to have this thing turn out worse than what its potential was. In any case, the pressure rating (which is a true objective measure of the storm) and the timing, as well as the landfall position, were off by relatively small amounts from the initial forecast, but all three combined contributed to the sparing of deep South Texas from "Claudette-a vu" which was the storm winding up with greater effects than what was portrayed in some circles.

However, that was not the only thing that did the trick. If there is one good thing about both Claudette and Erika, it's that they should teach the people who continue to pound away with the meteorologicaly unsound idea that one simply "tacks the forward speed" onto the right side of the storm to get winds. This is nonsense. The winds of the storm are determined by the structure of the storm. In the cases of Claudette and Erika, it was plain to see how the structures of both relatively quick-moving storms (remember the TPC error on both on landfall on 24-hour forecasts were over six hours, ours was less. Please refer to TPC forecast positions the day before the storm for verification. In addition, remember that listing something as a 24-hour forecast three to six hours later (in other words, a 4:00 p.m. CDT forecast should have a 4:00 p.m. verification time, not sometime before) seems to me to be a little bit out of line. But one can look the day before if one wants. The point is, the systems were moving 15-20 mph, yet both the storms were most developed in front and to the south of the center. Now why was this?

The answer is eyewall tightening. The approach of the storm from the east forces a tightening of the eye on its western side due to frictional and dynamic effects. The rain-cooled air over land, plus the tendency for the storm not to go inland, or at least slow, causes the eyewall to tighten and enhance convergence in the path of the storm. Think about it. We know the hurricane is a warm core system with a rapid increase in the wind toward the center, and hence the energy budget of the system. If it's this warm core that is driving the center, then the lack of friction over the water, the much more efficient feedback and the cooling of the air over land from rain must mean the differences between the warm core and the storm's western areas must increase. The rapid deepening is probably in response to this occurrence, as the eyewall tightens and the warm moist inflow from behind the storm continues. A storm paralleling the coast, though, would have the opposite happen; it would instead draw the cooler air in as it would have time to do it, weakening the left side of the storm. In any case, in both Claudette and Erika, the developed tightening of the one side of the storm changed the overall structure, and then this is whipped around quickly to the south side of the storm. Normally the wind will weaken on its left side due to imbalances created with a northward accelerating storm. With these storms, the winds were no longer aligned properly in a large part of the storm, meaning that the storms were stabilizing and so the turbulent transfer properties were not there to get the strong wind to the surface. The opposite side had the strongest structure develop, winds could have weakened on the very side of the storm that people would normally "tack on" wind speeds. In any case, the strongest winds and eyewall structure develop in the path and then south of the storm here. However, this will only happen for several hours with a steadily moving storm. Storms that stall or slow trying to come in will actually weaken after a while, as it gives time for the very processes that start the eyewall tightening in a short period of time to then infiltrate and weaken the eyewall. On the Atlantic coast, an example of the rapid deepening with a perpendicular hit is Hugo in 1989. Examples of weakening with slowing or stalling are Dora in 1964, Diana in 1984 and Felix in 1996. Felix wound up turning around and heading out, never hitting. The moral of the story is it's not the speed but the structure of the storm that accounts for the wind field. Hopefully clear thinkers will take these two storms for the examples they were, and we will hear less and less of this unsound idea, which to me is like using leeches to bleed patients if one was a doctor.

The lower Rio Grande Valley continues to be the "Jacksonville" of the Gulf as it is very difficult to hit that area directly from the east with a hurricane or tropical storm. In this case, it was simply a case of the upper high being a monster to the north, but if one looks at the history, we do find an avoidance overall of the area within 30 miles of the mouth of the Rio Grande. The last direct hit by a major hurricane was Beaulah. This of course was no major hurricane, but the last major threat was Brett in 1999 which was a category 4 that was forecasted by TPC 18-24 hours to move across the valley ala Beaulah (for accurate records of this, do not trust me, but go to forecasted archives by TPC. I do not want to be accused of saying something that is not true.) I point this out to show the difficulty in predicting a landfalling storm here. Brett, of course, along with Allen, moved far enough to the north and entrained enough cooler air by moving that way before turning inland to have their structures so that the valley was spared. By the way, it is noted that the TPC landfall forecast for the storm will verify very well in their forecast, since if one notices the probability charts are based upon the storm passing within 60 miles of the site. As someone who has lived in coastal south Jersey, 60 miles can make a huge difference given the different storm structures. In this case, a few hours and 30 miles also made a big difference. Had the storm been as slow as I thought, just a few more hours from the day before (Friday) or as slow as TPC had, which was a few hours after us, then we probably would have had it down at Claudette's pressure. But like Claudette, structure at landfall was also important, and these factors all worked to the advantage of the Texas side of the Rio Grande with this storm.

Ciao for now.

HURRICANE ISABEL REVIEW
by Joe Bastardi
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Isabel was the strongest hurricane to hit DIRECTLY from the southeast in North Carolina since the 1933 hurricane. The southeast here is defined as a direction that is increasing westward latitude at 1 degree or greater for every 2 degrees the storm is moving northward. The 1933 landfall was 60 miles farther north than the landfall with Isabel, which was midway between Cape Lookout and Cape Hatteras. Comparisons were made to the 1933 hurricane well in advance on this site, and will be made again in this review.

In writing this, I have decided to confront two errors made, one directly related to the storm and the other not. That latter one involved the assumption that Tropical Depression 14 would develop behind the storm, which it did not. However, its large-scale interaction with the upper pattern produced the result of turning Isabel to the west at a crucial juncture; the "bend" in the track that was forecasted. This is yet another example of the fact that the tropical system is a cork in the stream, reacting, then eventually interacting, with the pattern that produced it in the first place. That interaction is crucial in the final destination of the storm.

The "error" was the 5-day forecast for the hit at the mouth of the Chesapeake Bay. The 5-day TPC idea was farther down the coast, and indeed where it hit, which ended up being a difference of about 100 miles. This was truly an outstanding forecast. But the strategy on my part was that there were three areas this storm could make landfall; crescents of the coast that faced as much south as east. The northern one was the mouth of the Delaware to Point Pleasant, New Jersey. In 1903, a hurricane hit this area from the southeast, but was laughed off (for instance, in New York City) as nothing really happened up there, according to the New York Times. The second area was from Ocean City, Maryland, to the mouth of the Chesapeake. The 1933 hurricane hit just south of this area and caused hurricane-force wind gusts to New York City. Keep in mind that hurricane-force gusts occurred as far north as Pitman, New Jersey, and Lancaster, Pennsylvania, roughly the parallel mileage of the difference of the storm hit. The third area was between Hatteras and Cape Lookout. All three were listed as areas of possible landfall.

The forecast taking the middle ground was based on the worry that the turn to the northwest could be too little, too late. It is interesting to note that the reason the change was not made by me till Wednesday was that until then, the 3-day track I had was perfect. TPC was great also, it was off by about 60 miles at most, but the error was that it was farther east. A similar error continued that would carry the storm farther north, so until Wednesday the adjustment was not made. I feel strongly about not waffling on a forecast. Instead of adjustment with each passing moment, then claiming the closest to be right, I would rather keep out one forecast till certain, based on the weather, then adjust. This means that one cannot be accused of waffling in the wind, and that one lets the weather, not the models, dictate the forecast. In this case, the model, the GFS, did the best job of all, much like the Fabian endgame. This indicates to me that in large-scale systems we may be seeing the development of a reliable forecasting tool IF IT IS CONSISTENT. Before Monday, the 15th, the model was a study in waffling as one set of daily runs had hits everywhere from Brownsville to Newfoundland. This is not going to be criticized as it goes hand-in-hand with NCEPS disclaimer on it. However, the European started too far south, then swung too far north. The UKMET did the opposite. The Canadian was always east and gradually came to the right idea. Overall, from day five out, I consider this a GFS win.

So, I have confronted the error, one that was around 100 miles on five days after being near 0 on three days (this from the original landfall TARGET forecast issued Friday night on this site.) The forecast that it would get to 80 west was issued long before. In fact, it was issued the Tuesday before, some nine days in advance. So the error there on how far west this wound up was 0! This, I would hope for some of you out there, balances out the 9-day error on Fabian's westward point of 240 miles.

In fact, I was so confident of the hit in the mid-Atlantic states that when I was competing at the United States qualifier for the world team in bodybuilding on Sept. 13th, in my bio sheet for the competition, I had written my title at AccuWeather.com, and that I would be on MSNBC all week coming up because Isabel was going to hit the United states and come north at us (the show was held in Harrisburg.) I took a double risk because not only could I have wound up blown out of the competition (fortunately that did not happen) but also at that time there was still all sorts of speculation ranging from Florida to east of New England.

But yes, the original idea was too far north. But the strong points far outweigh this. Consider the following: The comparison to the 1933 hurricane. This was referenced over a half dozen times along with the idea that came out of Hugo and Hazel as to how far north a storm can come before it fades east of north. Much like the 1933 hurricane, Hugo and Hazel, this storm stayed west of north all the way to 40 north. It is yet another argument that areas from the southern tip of Delmarva to central New Jersey that lean north-northeast are not immune to a strong hit. Both the 1933 hurricane and this storm were very big storms, with category 3 pressures, but spread out. Hugo and Hazel were big, but deepening. All four storms ran to the trof position.

But it was the continued hammering on the 1933 storm and the parallel which I think set us apart. The 1933 storm, along with 1936 and most recently Felix, are what my dad has labeled short-cut storms; ones that do not arc, but come directly at the coast from the southeast. This offers a very different endgame for large areas of the coast to the north. Consider the ideas brought up about 1933. To have that track, one must have a huge high to the northeast, increasing the area of structural alignment aloft and expanding the amount of east to southeast wind with the storm. This is a much more dangerous component then the classic storm coming from the south, which if too close to the coast, has much of the energy to the west pulling apart the storm due to condensation in the colder air, and also the disruption and deflection of storm surge until at least New England. The exception to this was the 1944 hurricane, which I am convinced shot due north after Hatteras so the eyewall came onto the coast all the way to South Jersey, then took off northeastward. Southern New England was not hit near as bad with that storm as with Carol and 1938, which were storms that stayed out at sea to the east before slamming the coast. Gloria and Belle both hugged the coast from Hatteras northward and were torn apart. Floyd hit the coast, and because it was moving east of north, occluding processes that occur with a Hazel, for instance, a storm that is moving west of north AND STILL BRINGING WARM AIR TOWARD THE TROF do not allow the continuation of intensity. Belle, Gloria and Floyd illustrated Bob Case's idea (former TPC guru from the 1980s) that weakening storms by their nature do not have the correct alignment to bring down steady state-strong winds. I may add to that, that in the case of storms occluding, but moving west of north, there is still the increase in instability occurring, though perhaps through non-tropical processes that will allow for the turbulent transport in bands such as witnessed in Hazel and in Isabel. But the idea that a comparison to 1933 was warranted was verified with a vengeance when the truth came out about what happened around the Chesapeake Bay. Record floods from 1933 were broken.

I started on Tuesday opining that a similar occurrence to 1933 could be on the way, where heavy rain pouring downstream from rivers would be forced up against a southeast storm surge up a funnel-shaped bay. The classic situation here is Narragansett Bay in Rhode Island, but one shutters to think what would have happened to Providence had the extreme rain that fell with Carol and the 1938 storm over western New England had fallen farther east. Remember, as the structure of the storm changes, the area of heaviest rain shifts west of the path. It was bad enough that the funnel-shaped bay took the storm surge, but the amount of water coming southward was not nearly as great as it was west of the tracks of those storms where the cold air was aiding in precipitation processes (Providence.) But with Isabel, many people that wound up east of the path of the storm had initial overrunning heavy rain, and then the core of the heaviest rain went into the areas where rivers flowed to the bay, while the bay surge was coming north. It set the stage from Tidewater to Baltimore for what actually outdid the 1933 storm in many places.

I was puzzled at midweek as to why this wasn't being bandied about moe. In fact, you may have noticed in my writings that I was questioning the whole situation simply because I was trying to figure out why no one, besides us in the office, were yapping about this. Tuesday morning before the storm, Elliot Abrams and I were having our usual 3:30 a.m. chit-chat, and both of us were trying to find reasons that, given the track (and even with mine farther east up the Bay) that this wasn't going to rival or beat the 1933 storm from Norfolk northward. Of course, the rest is recorded history now. It did in many places. Pictures of Norfolk under water were very similar to the pictures of what happened in 1933. The big reason, again, is while storms have had stronger winds (Bonnie even may have had higher gusts and the 1944 storm had gusts to 156 at Cape Henry) the angle of attack pushed water in a very different way in these areas

Pressure and wind: I have received arguments, all of them from people who were not at the center of the action, that this storm was a weak category 2. The fact is that very little has been heard from the storm's prime landfall target, Hatteras, because no one can get in there. The place looks very hard-hit. In talking to people there that have ridden out hurricanes from the south, I've heard that this storm was simply beyond the scope of their imagination, worse than anything they had seen and something they would never do again.

I have often drawn parallels between hurricanes and humans, and hurricanes and various type of athletes. The young Isabel, the category 5, was like a dangerous boxer in his youth, capable of unloading a devastating single blow. The tight eye, screaming wind and low pressure were all the hurricane's equal of a boxer in his prime. However, even after his prime, a great boxer is still a champion. Isabel at landfall was like Ali in 1974; not the same as when he took the title from Liston, but still good enough to beat George Foreman. (If you have ever seen that Liston fight, you would see how unreal-fast he was.) He was older, wiser and still achieving the same result. By that I mean, given the abilities, Ali maxed out. The damage with Isabel, given the pressure and structure of the storm, maxed out. The storm's total damage will be what a 957 mb hurricane should deliver. If it were smaller and tighter, hurricane-force gusts would not have occurred 200 miles from the center. There may have been more extreme damage near the center had the eye been 10-miles wide, but the processes that caused the storm to affect so many people may not have occurred more than 100 or 150 miles from the center. So it's a moot point. 957 storms produce 957-type damage. It may not be as intense near the center, but it is more widespread.

Sort of like being jabbed into submission. If one does not realize such things, the amount of energy needed to sustain an eye 40-miles wide with a 957 pressure, then know it's the weather equivalent of having the rope-a-dope performed on you.

One fascinating aspect brought up by Elliot was the maintenance of strong, damaging winds away from the center of 90-100 mph at the same distance that they were when the storm was packing winds of 150 with a tighter eye. It's as if the extreme winds from the eye to 25 miles out disappeared and the new wide eye simply took over so that the winds to near 100 were always as far away from the center point as when it was strongest. The fact that this band must have had tremendous convergence probably stopped the storm from pulling the eye back in tight again. Like many an aging person, if one does not use it, one loses it, and it's tough to get it back.

The call for Isabel to become a major hurricane, like the call for Fabian to be one, came well before the Hurricane Center even classified it as a depression. This was one of those systems that one could look at the pattern and know it would develop. In addition, it was quickly noted it would move much farther west than Fabian. The call for the storm to at least get the United States (80 west) was made more than a week in advance, as we pointed out two major items: 1.) storms that bend back in their path are the long-tracked storms that usually make it, and 2.) the godsend of the typhoon in the Pacific which hit Korea, indicating the positioning of the southwest Pacific high, was very far west and teleconnected back to the Atlantic ridge being very far west. So the bend back to the west signaled the handoff through the mean Central Atlantic trof to the ridge to the west. And like its predecessors that went the distance, the Donnas, the Andrews and the Glorias, (and this was again pointed out) explosive deepening occurred once the storm turned to the west.

When that forecast was made, the modeling was forecasting a stall and a turn north at 70 west. In addition, my email-patrol had emailed me a startling statistic - only one storm out of 39 had hit the United States from where this was when my forecast was made. Well, now it's two out of 40. When dealing with storms and analogs, one can pull any rabbit out of the hat. For instance, which was the more important idea - the bend back to the west and the typhoon teleconnection, or the statistic saying there was less than a 3% chance of the forecast being right? Well, if one uses the first two, plus all the ideas from the hurricane forecast in the pre-season, one can see why the west set was chosen.

Another aspect of the storm was the post-landfall period, watching the strongest winds go to where the storms circulation lined up correctly so "bursts" of turbulent transfer could come down to the surface, and the heavy rain going to the area WEST of the track where colder air and the disruption of the circulation led to enhanced condensation processes. This is part of the whole "anti-theory" that debunks the "tack on the forward speed" idea. Wind and precipitation distribution are all structure related. Each storm differs at different times.

The landfalling Isabel also drives home the hurricane intensity forecast. That area of the nation was directly targeted in the early-season forecast based on the analog years and pattern recognition technique's that have been developed here as well as the only verifiable scale that can be used in a tangible way. The 14-plus rating given the Carolinas meant that the zone would be affected this year by storms that would pile up the equal to almost category 3 effects (16). The forecast and scale explanation is for all to read. The August update lowered it a bit to a mid-range category 2 and increased the threat to Florida. The point is that just as readers in Texas expected a hurricane hit, readers in the Carolinas using this idea expected a stronger one. And given the numbers in Florida now, so they should. But we will be able to say what right and wrong was, without abstract non-concrete and vague terms like "could threaten" or ranges such as 6 to 9. This will be in the summary at the end of the season. But it marks a triumph of research and pattern recognition and countless hours, non-paid, and on my own, to try to develop this so that people will have a meaningful pre-season idea of what to expect. My goal, of course, is to make this the mainstream go-to pre-season hurricane forecast. The levels have been upped immensely as far as the description of the season, but even with no new landfalls, this will mark the third straight season of demonstrative skill. Though, in many circles, I hear the slings and arrows of luck or voodoo whizzing by.

I take no pleasure in the misery of others, such as the misery caused by Isabel. But I feel strongly that through hard work I am on to something here that can give people enough of a heads-up about what is going to happen in a season relative to them that it does them a service. That is what it is all about.

THE LITTLE STORM THAT WOULDN'T DIE: TROPICAL STORM HENRI
by Joe Bastardi
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Henri became the fifth storm to traverse the Gulf of Mexico this year. It was yet another storm that was called for to develop over five days away on our site as the pattern was such that yet another hybrid would try to develop. The storm had to fight much dry air and borderline upper conditions its entire career. Its first landfall on the Florida coast, after reaching a pressure of 997 mb with 55 mb, was not even ranked as a tropical storm. The main aspect to Florida was heavy rain, and the rating in the zones was not even as a tropical storm, but a 1.5 and a 1 for zones 4 and 5.

The low-level circulation had its top completely blown off, and TPC pronounced it DOA on Monday, September 8th. I, however, did not buy this. The low-level circulation remained in tact all week and wound up stalled at 1005 mb, 150 south-southeast of Hatteras by Wednesday. The development of an upper low in the Tennessee Valley in the diagnosed trof split pattern forced ridging to develop over top of the system, and the system was back to minimal tropical storm intensity by the 11th. All the while this was ignored by Miami, until grudgingly it was referred to as a gale center, the remnants of Henri. To their credit, NWS offices from Wakefield to Philadelphia understood the tropical aspect of the storm, and on Thursday came into line with the AccuWeather.com idea that this would play a major roll in the Friday-Sunday weather on the East Coast.

Henri, like the last Henri to be named in 1985, actually telegraphed where a far bigger storm to follow was headed. The last named Henri in 1985 was another weak storm that suddenly came to life off the mid-Atlantic coast and wound up making landfall as a minimal tropical storm on Long Island. Several days later, Gloria followed. This year's version moved north-northwestward and inland on the North Carolina Outer Banks with 3- to 5-inch rain amounts into southeast Virginia, and wind gusts to 50 mph in the coastal waters. Tides ran 1-3 feet above normal. An arguable tropical storm at best, and only a sub-tropical storm rating of 1.5 for zones 7 and 8. Though tropical storm conditions did exist, I simply took the pressure at 1005 as the best indicator of the grade here so as not to be accused of trying to pad scores for the hurricane intensity scale. It was also pointed out that in light of Isabel, which, though almost a week a way we were already forecasting to be a landfalling high-scoring storm, that the way to pad scores was NOT to score it as a storm as Isabel would be a big scorer. I am saying all this because it is vitally important to me that the advanced ideas we have in landfall intensity be verified as objectively as possible. So a compromise was in order.

The real significance of Henri laid not in the storm itself, but with what it meant. It signified that the much ballyhooed ridge off the East Coast and the warm water feedback ideas were good and set the table for easier prediction of the final result with Isabel. It showed the folly of writing off any low pressure over 85-degree water. The air mass that the storm pushed in was as tropical as any we have seen, and that tropical air was in place Monday morning, the 15th, for an old convergence band in eastern Pennsylvania to activate with 10 inches of rain and record flooding.

It also once again demonstrated that, while TPC is getting better at major systems out of the deep tropics, systems that fall between the cracks and are not the pure tropical monsters that are better behaved overall because of the large-scale patterns that establish them, involve a great deal of attention to detail in the pattern. Once again the East Coast is being deluged by heavy rain as in 1999, last year and now this year. It is either done by way of major tropical systems when that water is so warm , or by systems that in past years would be thought tropical but now are classified according to a set of seemingly always-shifting sand. Once again, my proposal is that any closed rotary circulation with winds in excess of gale force in one or more quads should be named. Even if the strong winds are not quite near the center, the fact they are there and the water is warm means enough forced convergence so that they will eventually get there. The convenient way to justify Henri as non-tropical was never to send a plane back in to see if it really was warm core, though the surge of dew points to over 75, the calm center, and the winds reported by the actual public that got under the storm, make the argument for it. There are arguments against, but they are supported by ideas that could have easily been settled with one or two recons. Henri was every bit the storm Grace was at landfall, and in fact Henri had a better and more obvious rotation center and wind profile.

Such things may be considered petty on my part, but again, it made a big difference in the outcome of the weather in a large area for a 3-day period. More importantly though, the Henri this year was the warmup band for the main show, Isabel, much like the Henri in 1985 warmed the crowd for Gloria. Maybe Henri in 2009 will carve its own niche.

Ciao for now.

TROPICAL STORM GRACE REVIEW
by Joe Bastardi
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The season's 7th named storm and 6th since June 1st was Grace, a minimal tropical storm that exhibited many of the characteristics found in western Gulf hybrid storms and embryonic western Pacific developments.

While the storms that capture the fancy of many are the large, well organized African waves, the hybrid is something that must be dealt with also. The western Gulf origin storms are famous for their completely opened western side. In these cases often there are existing trofs that don't have the normal strong southeast flow that exists over Texas so the pressures are higher than average over the state. The trof aloft lowers pressures a few millibars in the Gulf, and then a tropical wave adds heat and that is what usually will develop, providing the upper feature backs away. This causes an increase in upper divergence from EAST to WEST over the system, so the place where there is low-level convergence and upper-level divergence is east of the low pressure, not west. Very often, several centers develop, but it is always the center to the north or northeast of the envelope that has the weather. The stronger shear west, plus the dry inflow from Mexico, leaves the west side open. Because the storm does not have five days over open water to develop (it develops close to land) it very often remains wide open to the west, while east and northeast of the center a tropical storm is occurring. Highest wind gusts with the system, when landfall was made between Galveston and Freeport, was 62 mph from a buoy south of the mouth of the Sabine reported to us by KDFM meteorologist Kerry Cooper, and this is so you know we are not trying to pad the stats here. As it is, the storm received only a 1.5 for its effect on Texas (2 is a minimal tropical storm, 1 a depression) and 1 for Louisiana. The fact is, though, that the wind needed to produce the type of wave action that occurred on the Texas and Louisiana coasts had to be of gale force, but in scoring this I don't want any accusations of padding scores, so overall with the two zones it got 2.5. For the overall cumulative intensity score, developed to truly judge the season rather than relying on more subjective looks, (it adds up all the sub 1000 pressures of storms) it received no points.

Grace was an example of something that we have seen before. The most outstanding debacle was a 1979 storm around Sept. 20th, Henri, which was over the southern Gulf and having bulletins issues on it when a smaller, tighter and much stronger center developed on the north side of the envelope and slammed Corpus Christi with 70-90 mph winds. Like Karen last year, despite dewpoints in the 70s and pressures that went down and up like a hurricane passage, it was not labelled as a storm at the time and was basically shrugged off as non tropical. More recently, in 1998, Frances, a western Gulf storm, was also constantly in a position of "reforming" north and made land well north of where the original tracking of the southern area of low pressure occurred. The DESIRE TO APPLY TRUE TROPICAL FORECASTING TECHNIQUES TO THESE SYSTEMS will never work unless the system wraps itself up. The farther west they develop, the more chance that will not happen, and the northern area should always be tracked. And, of course, there is Allison, which in some cases is still being denied as being a tropical storm.

Are they warm core? Well, yes, because the lower pressure farther northeast away from the colder upper feature indicates a warming of the system. Are the convenient storms that come from the east, like Claudette or Carla, ones that get a chance to draw from just true tropical sources? No. But get caught in a boat, or ignore them, (Allison was an example, too) and one gets burned. They are truly a challenge worth their own time, effort and scrutiny in the post-storm period.

Ciao for now.