Just when you thought Hurricane Ernesto was about to do that rapid intensification thing that we all grew so accustomed to last year with Katrina, Rita, Wilma et al., the exact opposite happened. Rapid stengthening? Ha! Try rapid weakening! As noted earlier, Ernesto was downgraded to a tropical storm at 5:00 PM EDT. What happened? Blame Hispaniola:

APPARENTLY…THE HIGHLY MOUNTAINOUS TERRAIN OF THE SOUTHWESTERN PENINSULA OF HAITI HAS DISRUPTED THE CIRCULATION OF ERNESTO. THE LOW-LEVEL CENTER HAS BECOME BROAD AND ILL-DEFINED…THE MINIMUM PRESSURE HAS RISEN TO ABOUT 1004 MB…AND THE HIGHEST OBSERVED FLIGHT-LEVEL WINDS WERE 42 KT. IT IS PRESUMED THAT STRONGER WINDS ARE OCCURRING IN THE NORTHEAST QUADRANT OF THE CYCLONE VERY NEAR THE COASTLINE OF HAITI. THE CURRENT INTENSITY IS SET…PERHAPS GENEROUSLY…AT 50 KT [60 MPH].

Dr. Jeff Masters explains further:

Ernesto is has been clobbering Hispanolia all morning with tropical storm force winds and torrential rains. But now, the island has bitten back. Ernesto is struggling to hold his eye together, thanks to the mountainous terrain on the southwestern peninsula of Haiti. The 1:10pm and 3pm EDT Hurricane Hunter eye reports found a surface pressure estimated at 1007 mb, a big increase from this morning’s 995 mb. Moreover, the eye was substantially tilted, with the calm at the surface about 25 miles south of the calm at the 10,000 foot flight level. The plane could find maximum winds of only 35 mph during that 2-hour period.

Ernesto should restrengthen somewhat as he moves away from land:

The upper level outflow still looks strong, wind shear is weak, and an upper-level anticyclone (clockwise-rotating region of winds) is still in place, so Ernesto will no doubt reorganize tonight once he moves away from Haiti. However, given Ernesto’s small size and the difficultly he is having with Hispaniola, there is hope that the expected 1-2 day traverse of Cuba will significantly weaken him.

Intensification will resume after the trek across Cuba, but how much of Ernesto will be left to restrengthen? SciGuy predicts: “[D]epending on how long Ernesto remains over Cuba, it may well emerge north of Cuba as a tropical storm, perhaps even a depression.” That would leave the storm with a significant uphill struggle to become a major threat again. Dr. Masters says: “It may take Ernesto a day or two to regain hurricane strength once he emerges into the Florida Straits. This bodes well for the Florida Keys, which may dodge another hurricane. I think that only if Ernesto makes landfall north of Tampa will he have time to organize into a major hurricane.”

Even so, I’m glad to hear that the evacuations have begun in the Florida Keys. You can’t be too careful with these unpredictable beasts. Remember: if the local authorities tell you to get the hell out, get the hell out! Simple as that.

P.S. Incidentally, the title of this post says Ernesto’s interaction with Haiti and Cuba is “good news for Florida,” and it is — but it certainly isn’t good news for Haiti and Cuba. At this point, Ernesto is more a rain event than a wind event, but particularly in Haiti, a major rain event is plenty bad enough. Only time (and damage reports) will tell, but Ernesto’s legacy could be widespread devastating mudslides in the deforested mountain areas of Haiti. Let’s hope not.

With the central Gulf Coast, including ultra-vulnerable New Orleans, now apparently out of the woods, the question becomes: could Hurricane Ernesto be the nightmare hurricane for the Florida Keys and/or Tampa Bay? With the caveat that we should be looking at the “cone,” not the track line, the forecast track and computer models are moving in a direction which makes that seem possible:

The good news is, land interaction with Cuba should interfere with Ernesto, and the water between Cuba and Florida doesn’t have as much heat potential as the water in the central Gulf:

Hopefully, all that will prevent Ernesto from become a truly intense hurricane — i.e., Cat 4 or 5 — as I feared it would on the previous track. Still, any major hurricane (Cat. 3 or above) hitting the Keys would be a Very Bad Thing, and I’m guessing a Cat. 3 hitting Tampa Bay probably wouldn’t be a walk in the park, either.

Again I should emphasize: it’s far too early to know exactly where this thing is headed, and everyone within the track “cone” should be making the requisite preparations.

UPDATE: Charles Fenwick says where Ernesto hits Cuba is important, and offers a cautionary note:

A huge wildcard in the intensity forecast is exactly where Ernesto goes into Cuba at. The official forecast takes it very near the highest point on the island, the 6750 foot high Pico Turquino. Hurricane Ella of 1958 went more or less square into it as a category three hurricane and came out as a tropical storm. Cleo of 1964 passed just to the south and went from a category three to a one in the process. If the future track of Ernesto were to go just as forecast, or ever so slightly to the right over the next 36 hours, then the weakening would probably be quite a bit more substantial than the forecast currently shows.

Other than that, however, there isn’t much impediment for Ernesto. The upper air enviroment is forecast to be extremely favorable for strengthening. The experience of Charley 2004 shows what can happen to a hurricane in a favorable enviroment, in spite of the seemingly limited space between Cuba and Florida. A track ever slightly left of the current forecast, keeping the storm mostly over water with the exception of a brief jaunt over the flat terrain in the center of Cuba would set up quite a worrisome situation.

And another cautionary note:

The scenario bringing Ernesto into peninsular Florida is the erosion of a mid-level ridge of high pressure that would otherwise push Ernesto to the west. It is the sort of scenario that the models are often too eager to forecast (such as was the case during Ivan in 2004). Because of that there is a chance for the forecast to get pushed back to the west somewhat, especially if the upper-air mission to be flown tonight found a stronger ridge than the models are depicting.

Meanwhile, Mark Sudduth summarizes what has changed:

Ernesto is a prime example of how tricky it can be to forecast a hurricane. Last night, it looked like the Florida panhandle could be directly impacted by Ernesto in about six days. Now, it looks like the Florida west coast could take a direct hit from the hurricane. Overnight, the global and regional models changed their tune fairly dramatically and have turned Ernesto sharper to the right of its original forecast track- thus greatly increasing the threat to Cuba, the Florida Keys and then the west coast of Florida. Even the Southeast, especially Georgia and the Carolinas will need to monitor Ernesto’s track as it may end up being a problem farther north as well.

The latest track takes the hurricane inland near Tampa on Thursday. Trust me, this is going to make national news as people will have to be evacuated that thought there was little threat from this hurricane. The exact track is going to be critical as Tampa Bay is highly vulnerable to storm surge- as is most of the west coast of Florida. The NHC currently forecasts a 90-100 mph hurricane making landfall, hopefully it will not be stronger. I am concerned about people being caught off-guard since this is quite a change from earlier thoughts, so it is important that people in Florida pay close attention to the future track of Erensto.

Much more, all of it well worth reading, from Dr. Jeff Masters and Margie Kieper (whose headline is: “This would be the wrong time for the FL Keys to hold a big party”).

I’m off to Shannon’s baby shower now, so updates will be sparse-to-nonexistent for the rest of the afternoon, unless they come from guestbloggers. But check out the links at top right — lots of great weatherbloggers and other info there, including of course the NHC.

The National Hurricane Center has upgraded Ernesto to a hurricane. Important sections of the NHC discussion:

LATEST RECON DATA INDICATE ERNESTO IS LIKELY UNDERGOING RAPID INTENSIFICATION. …

THE FLIGHT CREW HAVE BEEN UNABLE TO PROPERLY ASSESS THE MINIMUM SURFACE PRESSURE. THE SATELLITE APPEARANCE HAS BECOME QUITE IMPRESSIVE WITH LITTLE OR NO VERTICAL SHEAR NOTED ON THE SYSTEM NOW…AND CIRRUS OUTFLOW EXPANDING OUTWARD IN ALL QUADRANTS. …

THE OFFICIAL FORECAST TRACK HAS BEEN SHIFTED SIGNIFICANTLY TO THE RIGHT OR EAST OF THE PREVIOUS TRACK…ESPECIALLY AT 96 AND 120 HOURS..AND NOW TAKES ERNESTO ACROSS THE FLORIDA PENINSULA. …

THE GFS AND NOGAPS MODELS APPEAR TO BE ERODING THE RIDGE TO QUICKLY AND HAVE ERNESTO OVER SOUTHEASTERN FLORIDA IN 84 HOURS. THE REST OF THE MODEL GUIDANCE TAKES THE CYCLONE FARTHER WESTWARD OVER OR WEST OF THE LOWER FLORIDA KEYS. HOWEVER…ALL OF THE GLOBAL AND REGIONAL MODELS NOW AGREE ON RECURVATURE OVER THE EASTERN GULF OF MEXICO AROUND 96 HOURS…AND TAKE ERNESTO NORTHEASTWARD ACROSS THE CENTRAL OR NORTHERN FLORIDA PENINSULA BY 120 HOURS.

And here is the NHC forecast 5-day tracking map.

At 7:35 PM, InstaPundit linked to me with the tagline “IT’S ‘HURRICANE ERNESTO’ NOW.” When I saw that, I scrambled over to the National Hurricane Center website, to see if Glenn knew something I don’t know. But no, Ernesto is still a tropical storm, with 60 mph winds, as of 8:00 PM EDT. I’m guessing Glenn’s confusion comes from this AP article, which erroneously states:

As the first anniversary of Hurricane Katrina approaches, some residents prepared Saturday to evacuate amid forecasts of another hurricane entering the Gulf of Mexico. …

Gov. Kathleen Blanco said state officials were keeping an eye on Hurricane Ernesto, and the Army Corps was carefully tracking the storm’s movement, Lt. Gen. Carl Strock said.

The article is all over the Internet — and it’s completely wrong. Ernesto will probably be a hurricane soon, but it’s not yet. Where are the fact-checkers? Heads must roll! :)

P.S. For the latest on Ernesto, see the 8:30 update below.

UPDATE, 8:30 PM: Welcome, InstaPundit readers! Thanks for the link, Glenn! However, a correction is in order: [Glenn has now fixed the error -ed.] Ernesto is not a hurricane yet, despite what the Associated Press would have you believe.

Also… the computer models now appear to be clustering on a track taking Ernesto toward the eastern half of the U.S. Gulf Coast — somewhere between New Orleans and Florida — rather than Texas or western Louisiana. It’s far too early to say for sure, but here’s what SciGuy is saying:

The 4 p.m. forecast track update from the National Hurricane Center reflects a significant eastward shift in the computer models today.

This shift has occurred for two reasons. First, there’s now a bit of confidence that a ridge of high pressure over the northern Gulf coast will, indeed, weaken next week, allowing the system to move in a more northerly fashion when it enters the Gulf. Second, the storm’s center appears to have reformed northeast of where it was earlier.

All of this means that southeast Texas now faces a much lower chance of getting hit by Ernesto next week. It’s not time to signal the all-clear, but if tomorrow morning’s model runs confirm this trend we will probably be in pretty good shape. Unfortunately for others, the storm now appears likely to strike somewhere between New Orleans and the Florida Panhandle.

Here’s what the latest computer model tracks look like:

 
 
*** ORIGINAL POST BEGINS HERE ***
 
 
“Chances of Ernesto weakening now slim,” declares the Houston Chronicle’s SciGuy, Eric Berger:

Although it is too early to tell where Tropical Storm Ernesto will make landfall, it’s becoming increasingly clear that the storm will probably not break apart. As a result the entire Gulf Coast must be on alert because a powerful storm is likely to enter the Gulf of Mexico on Tuesday morning.

Overnight Ernesto has battled through some difficult wind shear, and instead of weakening it has strengthened to 50 mph winds. Its minimum pressure, a good measure of the storm’s organization, has also steadily dropped, and is now 997 millibars. …

There’s still a chance that wind shear, which should affect Ernesto for about another day, will impair its organization. But if the system remains strong by tomorrow night it will likely survive, and then thrive once it reaches the Gulf of Mexico next week.

And where will it go? Some of the most reliable models turn the storm northward, toward Mobile Bay or even northern Florida. The GFDL model, for example brings it to the Florida Panhandle by Thursday as a category-4 storm. In reality, the storm could land anywhere from Brownsville to southern Florida. The odds of a Houston-area strike, however, appear lower today than yesterday.

Alan Sullivan agrees with the notion of a more easterly track: “It may give New Orleans a scare, but I would bet on a turn toward the Florida Panhandle.” He also says:

Warmth runs deep in the waters of the western Caribbean. Explosive intensification is common there. In the past few years, several storms have spun to great intensity south of Cuba. Last October Wilma became the most violent hurricane ever observed as it passed through that area.

Here’s the map, from The Storm Track:

But, Sullivan points out, “It appears that Ernesto will track a little further north. It may actually cross western Cuba before entering the Gulf.”

As noted yesterday, the water in the Gulf is plenty warm, too. So, how strong will Ernesto get? Charles Fenwick says: “The peak of the intensification forecast by the intensity models have increased, with the SHIPS model raising the storm to 100 mph and the GFDL being more agressive, raising Ernesto to Category 4 strength at 140 mph. The official forecast is an average of the two.” Actually, it’s a conservative “average,” 115 mph.

Getting back to the track forecast… FLhurricane.com says an upper-level low in the northwestern U.S. holds the future of Ernesto’s fate. Unfortunately, the computer models can’t decide what to do with it. Fenwick writes:

I wouldn’t put too much weight on the forecast models until they are fed the upper air data collected by the GulfStream IV and that won’t happen until Sunday evening at the earliest. It would not be surprising to see the NHC continue their neutral hedge [splitting the difference and taking the average of the computer model forecast tracks] until then. People from the Big Bend of Florida to Texas should keep an eye on it this weekend and be thinking about the preparations that they would start making next week if Ernesto were to head their way.

Sayeth the SciGuy: “I’ll stand by my only prediction, however: we won’t know anything truly meaningful about where the storm is going until Sunday night or Monday.”

As of the 11am advisory, Ernesto has sustained winds of up to nearly 50 MPH. A Hurricane Watch has been issued for the Cayman islands, and Jamaica is under a Tropical Storm warning. It still seems likely that Ernesto could be become a major hurricane once he gets past Jamaica. I’ve also noticed that the center of the 5-Day Cone seems to get closer and closer to New Orleans. Of course, Ernesto could still get killed off by wind shear, and also, it’s a cone, not a line. Just saying that I’m starting to get a bit nervous for the Gulf Coast, and New Orleans especially.

Could we have a hurricane spinning and strengthening in the Gulf of Mexico, menacing the coast, on the one-year anniversary of Hurricane Katrina? It looks increasingly likely. Here’s the latest five-day forecast track from the National Hurricane Center:

It’s way too early to start seriously speculating about possible landfall locations… but, do you think the folks affected by Katrina and Rita are feeling a little nervous right now? Yeah, I think so too. (That said, everyone from Florida to Texas should be watching this thing closely. Five-day forecasts have a very wide margin for error, as the track “cone” indicates.)

The official forecast has Ernesto reaching hurricane strength on Monday, sitting on the borderline of Category 1 and 2 on Tuesday (the anniversary of Katrina’s landfall), and achieving Category 2 strength on Wednesday. And, as is the NHC’s wont when it comes to long-range intensity forecasts, those predictions are conservative: “MOST OF THE INTENSITY GUIDANCE INDICATES AN EVEN STRONGER INTENSITY.” It’s easy to see why. If the forecast scenario plays out as advertised, I don’t see what would stop Ernesto from become an intense hurricane:

CURRENTLY AN UPPER-LEVEL LOW IS SITUATED OVER EASTERN CUBA AND JAMAICA WITH STRONG WEST-SOUTHWESTERLY WINDS TO ITS SOUTHEAST. WATER VAPOR IMAGERY INDICATES THIS UPPER-LEVEL LOW IS MOVING RAPIDLY TO THE WEST-SOUTHWEST…AND THE MODELS ARE IN CLOSE AGREEMENT THAT THE LOW SHOULD END UP ALONG THE EASTERN COAST OF MAINLAND MEXICO IN 3 TO 4 DAYS. THIS SCENARIO SHOULD PROVIDE A VERY WEAK SHEAR ENVIRONMENT FOR ERNESTO TO STRENGTHEN…AND IN FACT THE SHIPS GUIDANCE FORECASTS THE SHEAR TO WEAKEN CONSIDERABLY IN 36-48 HOURS AND REMAIN WEAK THROUGH DAY 5.

The Houston Chronicle’s SciGuy says Ernesto could still fall apart before becoming a major threat, a la Chris:

The next 24 to 36 hours are critical because there’s still a good chance wind shear can tear the storm apart by Sunday. But if it continues to strengthen and remains intact by Sunday night, the system will be a threat to all points along the Gulf.

Potentially, a very serious threat. A well-developed tropical cyclone + minimal wind shear + the Loop Current = trouble. Yikes. Stay tuned.

P.S. Charles Fenwick is emphasizing the track forecast error margin:

The models are in excellent agreement for the first two days of the forecast, but diverge significantly after that. One shouldn’t put much weight in the track forecast after that, Because it’s just a hedge of the different model outputs, it doesn’t favor any of them. 5 day forecasts always have a large amount of uncertainty in them, but it’s even moreso in this instance. Everyone on the Gulf coast should keep a bit of an eye on Ernesto this weekend to see how the forecast evolves and be thinking about what preparations they may need to make during the early part of next week.

Dr. Jeff Masters has more.

P.P.S. Quoth Margie Kieper:

Just sit tight and make a plan, and try to chill for the weekend, and do not look at the CONU 26/0000Z. There’s no way to know until Sunday evening exactly how this is going to shake out, and what we’ll be expecting on Tuesday, but it will likely be something a little more complex than an anniversary.

P.P.P.S. The Storm Track has much more, including this map and description of the warm waters that lie ahead:

By using radar altimeters aboard satellites, we can actually see an expansion of the ocean and higher sea levels where there are deep layers of warm water. One such deep layer is positioned just south of Louisiana at this time. Oceanographers call these features “warm core rings” and they are nothing more than warm parcels of water that break off of the Loop Current near the Florida Keys and drift northward towards Louisiana and eventually westward towards Texas. This particular warm core ring is extremely strong and would provide an incredible amount of energy to any hurricane that would pass over it. Warm core rings weaker than this one were responsible of the very rapid strengthening observed in hurricanes Opal, Katrina, and Rita among others. If Ernesto were to drift over this warm tongue of water with favorable atmospheric conditions, as are currently being forecast at that time, Ernesto could undergo a very rapid strengthening. It is worth noting that a similar feature is noticeable to the south of Cuba in the previous map.

As I said: Yikes.

UPDATE, 4:37 AM: In the 2:00 AM EDT public advisory, the NHC says, “…AIR FORCE PLANE FINDS A BETTER ORGANIZED ERNESTO…” The wind speed remains the same for now (45 mph), but the pressure has dropped from 1003 mb to 999 mb. Hopefully the 5:00 AM advisory will clarify matters.

UPDATE, 4:50 AM: The 5:00 AM discussion says:

AN AIR FORCE PLANE HAS BEEN INVESTIGATING ERNESTO AND FOUND THAT THE CENTRAL PRESSURE DROPPED TO 999 MB WITH A WELL-ESTABLISHED CYCLONIC CIRCULATION. HOWEVER FLIGHT LEVEL WINDS HAVE NOT INCREASED MUCH SINCE THE PREVIOUS FLIGHT.

So, “better organized,” but not stronger… yet.

The intensity forecast has been nudged again toward faster and greater strengthening. Ernesto is now expected to be a hurricane by Sunday night, a Category 2 by Tuesday night, and a Category 3 by Wednesday night. That’s right, the NHC is now officially predicting that Ernesto will become a major hurricane. The discussion explains:

ERNESTO HAS BEEN A FIGHTER AND HAS BEEN ABLE TO SURVIVE THE STRONG SHEAR SO FAR. UNANIMOUSLY…ALL GLOBAL MODELS DEVELOP AN UPPER-LEVEL RIDGE OVER ERNESTO…A PATTERN WHICH IS CONDUCIVE FOR STRENGTHENING. THIS UPPER-LEVEL PATTERN COMBINED WITH THE VERY WARM WATERS AHEAD OF THE CYCLONE COULD LEAD TO SIGNIFICANT STRENGTHENING OVER THE NEXT FEW DAYS. THIS COULD RESULT IN ERNESTO BECOMING A POWERFUL HURRICANE IN THE GULF OF MEXICO. THE INTENSITY FORECAST IS LOWER THAN THE GFDL AND VERY SIMILAR TO SHIPS AND FSU SUPERENSEMBLE. OF COURSE…THE INTENSITY FORECAST IS HIGHLY UNCERTAIN AND STRENGTHENING MAY NOT OCCUR AT ALL IF THE SHEAR DOES NOT DECREASE.

Things could change, but my gut tells me this is the real deal. The NHC seems to feel the same way, judging from the ominous closing like of the discussion:

IN SUMMARY…ERNESTO COULD BECOME A POTENTIALLY DANGEROUS HURRICANE AS IT MOVES ACROSS THE NORTHWESTERN CARIBBEAN SEA AND THE GULF OF MEXICO. INTERESTS IN THESE AREAS SHOULD CLOSELY MONITOR THE PROGRESS OF THIS SYSTEM.

The latest post in Jeff Masters’ Blog indicates that TD 5 will be announced as Ernesto in the NHC’s 11am advisory. The storm is heading west quickly towards Jamaica, and may eventually become a threat to the Gulf Coast. The deciding factor appears to be a large area of wind shear (50 knots or so) near Jamaica that is heading off to the west, but much more slowly than TD 5. If TD 5 catches up with it, it may weaken and die. The wind shear is associated with a upper level trough of low pressure. This through is expected to split on Monday, and then an area of much lower wind shear will form. So the timing of TD 5’s arrival in the Carribean appears to be everything at this time.

Tropical Depression #5 has formed near the Windward Islands. This is that same storm that has been getting more attention lately than Debby.
Read the latest advisory here.

In a comment on my previous post about “proto-Ernesto” (a.k.a. Invest 97L), “tree hugging sister” writes: “Dr. Masters is now saying a new center of circulation has formed about 100 miles north of the old one, removing the South American coast as an impediment to development. Peachy.” She’s right. Sayeth Dr. Jeff at 12:17 PM EDT:

An important development has occurred in the past two hours–a new circulation center developed near 12.5N 63W, about 100 miles north-northwest of the original center near the South American coast. This new center lies between St. Vincent and Grenada, and southwest winds observed last hour in Grenada confirms that a closed circulation now exists at the surface. [This would seem to suggest that proto-Ernesto will likely be designated quite soon as a tropical depression or storm by the NHC. -ed.] The old center near the South American coast now looks likely to dissipate. Inflow of warm, moist air into its center was too restricted by the presence of the South American land mass, and thus a new center farther north along the axis of this tropical wave was able to form and take over. …

The separation of its center from the coast removes the primary impediment to intensification for 97L. It looks more likely that this storm will develop into at least a strong tropical storm, and probably a hurricane. The track such a hurricane might take is highly uncertain, but the more northerly center increases the risk for Haiti, the Dominican Republic, the Bahamas, and the U.S. East Coast.

Dr. Masters also says the next few hours are crucial to proto-Ernesto’s future:

What happens in the next few hours in crucial in determining if we have a serious hurricane to worry about in a few days, or just a another harmless tropical blob. The storm is very vulnerable to wind shear right now as it reorganizes. The center of circulation is almost completely exposed, with just one spiral band of heavy thunderstorms connected to the northeast side of the center. Upper level winds out of the west are creating about 10 knots of wind shear over the center, keeping the band of thunderstorms pushed to the downwind side of the center. If the shear can increase a little this afternoon, it may disrupt the storm enough to keep it from developing today. The new center location also puts the storm closer to the large area of dry air and Saharan dust that covers much of the eastern Caribbean. This may also help disrupt the storm.

However, I think 97L will overcome these obstacles. Wind shear is probably low enough to allow the storm to reform, and I wouldn’t be surprised to see the center jump again more to the east, to be underneath the strongest thunderstorms. The shear is forecast to remain low through the next five days. There is a zone of very high shear to the system’s north, but it is forecast to retreat to the west ahead of the developing storm.

Stay tuned.

While Tropical Storm Debby swims with the fishes, all attention is focused on a blob of clouds just east of the Lesser Antilles that is, for the moment, designated only as “Invest 97L” — or, as I’m calling it, “proto-Ernesto.” (Not quite as catchy as “proto-Alberto,” but close.)

It is passing strange to see an “Invest,” a mere “proto” storm that hasn’t even been designed as a depression yet, getting more attention than a named tropical storm that is expected to become the season’s first hurricane this weekend. And indeed, that a storm like proto-Ernesto is getting MSM coverage at all is decidedly a post-Katrina phenomenon; no “Invest” would have merited a Reuters article last year, or in previous years. But the level of attention does make some sense. As Mark Sudduth of Hurricane Track explained last night:

Debby is not of much concern to any land areas and should continue to move on out to the open ocean as it slowly intensifies. … No matter how strong it gets, it will not be an issue for anyone except shipping interests.

Of greater concern now is the tropical wave/low pressure area that is approaching the Windward Islands. It looks as though this will go on and develop in to a tropical depression and likely a storm. In fact, the GFDL computer model shows it becoming a strong hurricane as it heads in to the northwest Caribbean Sea. Even the NHC’s intensity model shows this becoming a hurricane. Needless to say, we will want to keep a close watch on the future of this system.

It’s far too early to speculate about track details, but the computer models show Ernesto approaching the Gulf of Mexico in 5 or 6 days. And let’s not forget about what’s happening with the Loop Current… yikes. So this potentially could be a problem for somewhere along the Gulf Coast late next week or next weekend — just a few days after the anniversary of Hurricane Katrina.

Here’s Dr. Jeff Masters’s take:

A powerful tropical wave that has the potential to become a serious hurricane is sweeping through the southernmost Lesser Antilles Islands today, bringing tropical storm force wind gusts and heavy rains. Barbados reported sustained winds of 32 mph at 5am this morning. Togabo had wind gusts to 36 mph, and wind gusts to 43 mph were observed on St. Lucia. A QuikSCAT satellite pass from 6:30am EDT shows a large area of 35 mph winds to the north of the center, which appears to be near 11N 59W, near the islands of Trinidad and Tobago and just off the South American coast. The storm’s organization has steadily increased since yesterday, and the Hurricane Hunters are tasked to investigate this afternoon to see if a tropical depression has formed. …

Wind shear is favorable in a small area over the storm–5-10 knots–and is forecast to remain low through the next five days. However, there is a zone of very high shear to the system’s north, so the forecast of low shear could easily change. A large area of dry air and Saharan dust covers much of the eastern Caribbean, and may be a modest impediment to intensification. The primary difficulty for the storm lies in its close proximity to South America. The storm center may hug the coast through Saturday, limiting its development. The storm should bring heavy rains and winds near tropical storm force over the ABC Islands of Aruba, Bonaire, and Curacao on Friday. After that, there is a lot of uncertainty.

The latest 8pm and 2am EDT computer model runs have a variety of solutions. The Canadian model continues to be very consistent and very gung-ho, developing 97L into a strong tropical storm on Saturday, south of Jamaica, then taking the storm into the Gulf of Mexico as a hurricane. The NOGAPS model is also consistent, assuming a more southerly track will occur with no development due to close proximity to the South American coast. The GFS takes a weak tropical storm across the Dominican Republic on Saturday, then into the Bahamas. The GFDL has the same idea, but has a much stronger system that becomes a Category 1 hurricane in the Bahamas on Monday.

The run-to-run consistency of the GFDL has been poor, and both the GFDL and GFS have not done a good job forecasting the initial track of the storm so far. A more southerly track betwen Jamaica and Honduras like the Canadian and NOGAPS models are suggesting is probably more reasonable. If 97L can survive the next two days and separate from the South American coast–which it has at least a 50/50 chance of doing–I believe it will probably develop into a serious hurricane, as the GFDL and Canadian models have been suggesting. The track such a hurricane might take is highly uncertain, but it appears that Jamaica, Cuba, and the Yucatan would be at highest risk in the Caribbean. No part of the U.S. coast can be ruled out as a target in the longer term.

Got travel plans to the Caribbean this week? Don’t change them yet. This appears to be an all-or-nothing kind of situation, and we could get nothing. It may not be until Saturday that we have a reasonable idea if this storm will be a major threat.

Whatever the long-term future of Invest 97L, Bryan Woods at The Storm Track makes the broader point: “It looks like the tropical season in the Atlantic is finally starting to pick up, and right on time, too.” If the NHC does declare proto-Ernesto a tropical depression or storm sometime soon, we’ll have two tropical cyclones spinning in the Atlantic for the first time this season. And probably not the last.

Tropical Storm Debby is slowly strengthening over the eastern Atlantic, but with the forecast sending her out to sea without ever “doing” Dallas, Houston, New Orleans, Miami or anyplace else, it looks like Debby will be a non-issue for us landlubbers — and attention is now turning to a blob of clouds that isn’t even a tropical depression yet, let alone a named storm (which isn’t stopping me from calling it “proto-Ernesto”). Dr. Jeff Masters explains:

Forget about newly-named Tropical Storm Debby, now churning west-northwestward into oblivion in the open Atlantic. The area we need to focus on today is a tropical wave near 10N 53W, about 500 miles east of the southernmost Lesser Antilles Islands. This new wave is a threat to develop into a tropical depression later this week, once it crosses into the Caribbean. NHC has assigned this disturbance the name “Invest 97L”, and has tentatively tasked the Hurricane Hunters to investigate it on Thursday afternoon.

While the wave does have the potential to eventually become a serious hurricane, it also has a number of hurdles to overcome, and it is more likely that it will never become a hurricane.

Read the whole thing. The Palm Beach Post’s Bob King has more.

P.S. Heh.

It was named at the latest (11p EDT) advisory. Everything the NHC has on it can be found here.

UPDATE BY BRENDAN: Mark Sudduth at Hurricane Track says of Debby: “There is not much to discuss regarding the 4th named storm of the year. It might become a hurricane and it looks like it will likely move on a path that will keep it away from any land areas. So - good news with Debby.”

In addition to Debby, there is also a tropical wave east of the Lesser Antilles that could become Tropical Depression 5 soon, and might potentially become a bit more threatening to land areas, though it’s far too soon to say how much so, or where. Anyway, here’s a satellite view where you can see both Debby (center) and proto-Five (left):

As predicted, the tropics are finally getting active.

On a somewhat related note, I want to again recommend Margie Kieper’s blog, which is running an excellent series of posts in the run-up to Hurricane Katrina’s anniversary, detailing the devastation all along the Gulf Coast. It’s the “hidden coastline” revealed. Definitely worth checking out, especially for those who came here after watching Spike Lee’s movie.

I am very, very happy to see this article written by Reuters. I hope it gets widely picked up. People need to understand how much worse Katrina could have been, and how many other, more severe threats — to New Orleans and elsewhere — still exist.

Because I think it’s really important, I quote the whole thing:

If you thought the sight of New Orleans flooded to the eaves — its people trapped in attics or cowering on rooftops — was the nightmare hurricane scenario, think again.

Max Mayfield, director of the U.S. National Hurricane Center, says there’s plenty of potential for a storm worse than Hurricane Katrina, which killed 1,339 people along the U.S. Gulf coast and caused some $80 billion in damage last August.

“People think we have seen the worst. We haven’t,” Mayfield told Reuters in an interview at the fortress-like hurricane center in Florida.

“I think the day is coming. I think eventually we’re going to have a very powerful hurricane in a major metropolitan area worse than what we saw in Katrina and it’s going to be a mega-disaster. With lots of lost lives,” Mayfield said.

“I don’t know whether that’s going to be this year or five years from now or a hundred years from now. But as long as we continue to develop the coastline like we are, we’re setting up for disaster.”

Looking back nearly a year to the costliest natural disaster in U.S. history, and the third-worst hurricane in terms of American lives lost, Mayfield said Katrina itself could have been a greater disaster. [Not just greater… far greater. Tens of thousands of deaths greater. -ed.]

More than two days before Katrina struck the Gulf coast August 29, the hurricane center had predicted its future track accurately and also warned it could become a powerful Category 4 storm on the five-step Saffir Simpson scale of hurricane intensity.

New Orleans was squarely in the danger zone, and emergency managers and residents had plenty of time to prepare.

“One of my greatest fears is having people go to bed at night prepared for a Category 1 and waking up to a Katrina or Andrew. One of these days, that’s going to happen,” Mayfield said.

Katrina went just to the east of New Orleans, sparing the city the worst of a massive storm surge and the strongest winds. But the city’s protective levees failed.

The worst-case hurricane scenario? Mayfield has many in mind. A stronger hurricane closer to New Orleans. A direct hit on the vulnerable Galveston-Houston area, the fragile Florida Keys or heavily populated Miami-Fort Lauderdale.

Or how about a major hurricane racing up the east coast to the New York-New Jersey area, with its millions of people and billions of dollars of pricey real estate?

“One of the highest storm surges possible anywhere in the country is where Long Island juts out at nearly right angles to the New Jersey coast. They could get 25 to 30 feet of storm surge … even going up the Hudson River,” Mayfield said.

“The subways are going to flood. Some people might think ‘Hey, I’ll go into the subways and I’ll be safe.’ No, they are going to flood.”

Mayfield, a silver-haired, 34-year veteran of the hurricane center who became its public face in 2000, is a tireless campaigner for hurricane preparation, warning the 50 million people who live in U.S. coastal counties from Maine to Texas that they are all in the path of a future storm.

He is mystified by a study that found 60 percent of people in hurricane-prone U.S. coastal areas have no hurricane plan — which to disaster managers means up to a week’s worth of food and water squirreled away, a kit with flashlights and other gear, and an established evacuation route to higher ground.

“After Katrina and after the last two hurricane seasons you can’t understand why more people are not taking hurricanes seriously,” Mayfield said.

Katrina, he says, killed people who stayed in their homes with confidence because they had lived through 1969’s Hurricane Camille. Camille was a much stronger storm than Katrina when it crashed ashore in Louisiana and Mississippi as one of only three Category 5s to hit the United States in recorded history.

“There were a lot of people who lost their lives because they thought that they had already lived through the worst they could possibly live through,” Mayfield said.

“Experience isn’t always a good teacher.”

(Hat tip: Susan M.)

Why hasn’t Tropical Depression Four strengthened into Tropical Storm Debby yet? Blame Canada Africa, says Adam Moyer at The Storm Track. More specifically, blame Saharan dust, represented by orange and yellow in the map below:

Charles Fenwick concurs. He also says T.D. 4 may be upgraded to T.S. Debby (thus retroactively making the alliterative, evocative title of this post actually accurate!) at 5:00 PM. Stay tuned.

UPDATE: Nope, still a depression. The title of this post remains inaccurate. But I don’t care! :)