07/05/05 -- TALK: Hurricane Dennis

The 11AM discussion of TD Four bumps it up to TS Dennis. This is the first one to form outside of the GoM this year. I'm not too hip on my tropical history...is it common for the Gulf to dominate the early part of the season? This is also the earliest the Atlantic basin has had 4 named storms, per TPC. If you'll recall 2004, Danielle didn't come around until August (nor did Bonnie and Charley), so this year is well ahead of last year's pace.

Right now, the offical forecast strengthens Dennis to a hurricane and then takes him over Cuba. It looks like, at this point, Dennis will head for the FL panhandle area...but that's a good week out, at least. Dennis' track is a little east of Charley's last year...so time may bring him closer to the Florida peninsula. Barring thermonuclear war, this will be the first tropical system with enough time and water to really get cranked up, so it should be a good one to watch.

It's looking rather interesting already; there's much sharper outflow than Cindy's (more shear?) and you can already see a kind of eye. This one ought to be interesting, indeed.
its july 5 and we are on D. Thats pretty unusually, I believe.

Dennis has time over moderatly warm water and low shear, so its prospects of organizing into a hurricane are better than the previous storms. This is really the first interesting storm of the year. I'll be watching this one... although I still think its too early in the season for anything large.
its july 5 and we are on D. Thats pretty unusually, I believe.

First time since close records began, apparently.

11 AM EDT TUE JUL 05 2005

Last time there were 4 named storms before July 15 was 1959. However, this says nothing about this season being more active. For example, 1997: 4 named storms by the end of July, but a really quiet season overall. Of course, that was during an El Nino year, so naturally, Atlantic tropical cyclone activity would be supressed. This year, we don't have that, so chances are, we will have an active season. Overall convective activity over the tropical Atlantic and the Caribbean have been abnormally high for June and July. If it weren't for harsh upper-winds, we would have gotten even more storms already. You can see a hint of the Saharan Air Layer in the deep Atlantic right now, so that indicates an inversion, something equivalent to a giant cap over that area right now (hence, not much activity between the Leeward Islands and Africa).

Dennis is sitting under the upper-level Sub Equatorial Ridge, which is very favorable for development, and the TUTT low just north of it is helping with the outflow. However, if it moves too fast, it may get under the Subtropical Ridge over Cuba/Florida that is subsident, so it would tend to inhibit rapid development. But for now, Dennis has the greatest potential out of all the storms that we have seen this year. It could very well be our first hurricane within a couple days.

And yes, the Gulf and northwest Caribbean are normally most active in June. In July, you get some development to the east of Florida and the east of the Leeward Islands, but new research has shown that the northwest Caribbean temporarily quiets down in July. The Gulf still remains active in this month.
Well according to my statistical search, it appears that in the July calendar month, there is on average 1 HURRICANE (not tropical storm) that forms outside of the Gulf every 1 or 2 years, so it's not horribly unusual, but there wasnt one last year, so it's on the outside of those stats.
18Z GFDL takes Dennis' 950 mb winds to category 4 strength before it hits cuba...might be overdoing the weakening as it crosses Cuba (its rather thin after all). NHC is forecasting it to reach major hurricane status now as of 10 PM advisory with category 3 strength invof Cuba.

...Alex Lamers...
Yeah, Dennis is about ready to take off. There's nothing going against it right now. Cuba's affect on it would depend on where it ends up hitting the country. Eastern Cuba is mountainous, so that would do more to disrupt the circulation. If it crosses western Cuba, then yeah, nothing much in the way of a disruption would happen, and it would continue plowing along as a major hurricane. This could be bad news for Florida residents......again. I'm imagining either an Ivan or a Charley track with this thing.
Heh...gotta love this from the recent discussion:


Looks like they are really playing this one up, with a steady intensification with the reorganization of the deep convection at the core of the system. Looks like 72 hrs will be the max (relatively, forecasts only go 120 hr) of 100 KT sustained surface winds. Ouch.

Yeah, New Orleans isn't going to be too happy...lol

Looks like the first look at an organized eye on the IR imagery. Really tight right now, so expect it to widen as the circulation increases.
Id imagine the layer of warm water cant be all that deep since it is early. I wonder how long an intense cane could last this time of the year before its waves mix up too much cooler water. Its moving pretty good now but it will likely slow down when the steering currents decrease as the ridge weakens for its turn towards the north.

the 06/00Z gfdl keeps it pretty intense the whole way... if that plays out it this one might be worth the long chase(im in boston not florida right now).
5 AM discussion has it becoming a Cat 3 in 72 hours. Possibly reaching cat 4 strength after that. Anyone know what the Gulf of Mexico water temperatures are like?
The waters are consistently warm, around the 80s; you can check the image here.

Dennis certainly looks more organized — there look to be concentric rainbands developing now; the latest discussion is calling for it to slow down, so I'd say we'll have a hurricane on our hands by the end of the day.
Dennis is looking very organized this morning with symmetrical convection already wrapping around a tightly stacked cyclone SE of Jamaica. I still like the NHC track a bit, but I do believe due to the ridge being cut a bit that this track will move further west as Dennis crosses into the Gulf of Mexico. Looks like I will definately be feeling the effects of Dennis here early next week in my Central Alabama location.
This storm has the potential to really mess up oil production in the Gulf. If the rigs are shut down for a significant amount of time than you can expect gas prices to surge. Worst case scenario would be extensive damage in Port Fourchon where millions of barrels of crude get unloaded. The official TPC track throws this potentially powerful storm into Pensacola which is already beat up from Ivan. Western outlier models including GFS are aiming for the Big Easy. Seems like every year a system threatens that area only to hit just east or west.
This storm has the potential to really mess up oil production in the Gulf. If the rigs are shut down for a significant amount of time than you can expect gas prices to surge. Worst case scenario would be extensive damage in Port Fourchon where millions of barrels of crude get unloaded. The official TPC track throws this potentially powerful storm into Pensacola which is already beat up from Ivan. Western outlier models including GFS are aiming for the Big Easy. Seems like every year a system threatens that area only to hit just east or west.

Very good point, Justin. That is the last thing we need around here is our gas and electricity prices to skyrocket once again. The Pensacola coastline is still gone since Ivan took most of it out last year. The beach area still sits facing the wrong side of the highway now, and a storm of this proportion would take out the rest of the condos in the region. This would probably drive people from rebuilding if another storm of that magnitude hits there anytime soon.
SST's are abnormally warm this time of year, everywhere in the Caribbean and Gulf 1-3 degrees C above normal this time of year, so there would be no problem sustaining a major hurricane. Plus, Dennis isn't going to be stalling out and sitting in the same place for more than a couple hours, so mixing of the water won't be an issue. If shear is totally absent, I would not be surprised if the storm strengthens beyond 100 kts. The ridge does look like it's remaining firm, so a track somewhere between New Orleans and the Florida panhandle looks the most likely at this point. It would all depend on the shortwave coming through in a couple days.

And I would certainly hope the latest GFS run isn't going to come true, because the right front quadrant of a major hurricane crossing into Lake Pontchartrain would be New Orleans' worst nightmare.
If Dennis passes just to the east or just to the north, New Orleans could be hit just as badly. Lake Pontchartrain is just to the north of New Orleans, and a northerly wind on a back side of a storm would push the waters of the lake right into New Orleans.

In my opinion, I think the storm is going to strengthen beyond the NHC forecast. It has already shown to be ahead of the NHC's schedule from yesterday, I can only imagine the newer forecasts may suffer from the same issue of time.

I figure, this far out, that the storm will take on a Charley/Ivan path that may undoubtedly bring it ashore between Pensacola and New Orleans. I don't think I have to explain how bad the situation would be if it hit either town.
I think New Orleans would be more afraid of easterly winds than northerly. Offshore winds would typically be lighter, so even though New Orleans is south of the lake, it shouldn't be as much of a conern than the extremely strong easterly winds that would come ahead of a storm from the south. Water would just pile up into the lake from the Gulf, and the immense storm surge would do its thing with the city. Well, someday, either this weekend or a hundred years later, something like this will happen to New Orleans, so anyone who lives there should keep their eyes out.
Is it just me, or is it highly unusual for a hurricane this strength to be forming this early in the season? Doubtless this has happened before, but it still is pretty rare. This does not bode well for the rest of the season. If we are having a possible Cat 4/ dare I say maybe even Cat 5 in early July, what will August and September be like??? :shock:
According to the NHC the SST's in the Gulf and the Carribean are already 1-3 degrees Celsius above normal. How hot will they be in late August/early September?
This may be the year that the U.S. mainland sustains another direct hit from a Cat 5 storm. :evil:
At this point, after looking at all the models and analyzing the NHC discussions, Dennis looks like it might be the next Camille. Except a month earlier. The potential path similarities are very eerie. :shock: :shock: And quite a few of the models are pulling for a more northwesterly track, especially the GFS 132 hour 850 millibar, which shows Dennis plowing into New Orleans around 1200 UTC on Monday. If it follows this potential track and strengthens as much as everyone thinks it will, there well could be the largest hurricane evacuation in U.S. history come this weekened. Anyway you look at, whether it be the Big Easy, Biloxi/Gulfport, Mobile, or Pensacola, this could be a major disaster. This could be the big one everyone has talked about for years. Stay tuned. :!:
Except for Hurricane Audrey in 1957 (June), there were no U.S. landfalls of cat. 4 or higher in either June or July. Since 1851, the numbers for U.S. landfalling hurricanes in July are as follows:

Cat 4-5: 0
Cat 3: 3 (1936 in Florida, 1916 in MS/AL, 1909 in Texas)
Cat 2: 6
Cat 1: 14
Total: 23

So the last major hurricane to hit the U.S. in July was in 1936! Dennis could be the first cat. 4 storm to hit the U.S. in all the July's on record. Cat. 5 may be pushing it, but it's not impossible with the current atmospheric conditions in play.
Major hurricanes in July are not that common because the upper level winds have a tendency to become unfarvorable in the carribean during the month of July, the water temperature usually does not peak until early August, but it looks as though it has already gotten up around peak levels in some parts of the gulf and the upper levels have become favorable much earlier this year. The potential is there for a historical year. Great for chasing but not the communities that get devistated. I grew up about a 1/2 mile from lake Ponchatrain in Mandeville and it does not take much for flooding to occur on the north side of the lake because their is no levy just a 3 foot retainer. If the eye were to hit New Orleans it would devistate the communities of Mandeville and Slidell. If the eye were to move WNW over Lake Ponchatrain it would obliterate New Orleans. The hurricane would push water into the Lake and New Orleans and when the wind shifts and starts blowing out of the north it would fill New Orleans up like a bath tub. It is only a matter of time before this happens, I just hope it is not this year. All the water that falls in New Orleans has to be pumped out so it would remain flooded for a long period and disease would become a major concern. Here is an article.


I just got home from Cindy and she was a good warm up for Dennis. The path Dennis is forecasted to take is very similar to Camille and with nothing forecast to hamper developement it could be just as bad. There is no good place for this thing to hit, but if I had to chose I would send it to gulfport since it could really use a facelift and the casino's would help things get built back quickly plus it is a really good place to watch a strong hurricane roll in with well buit parking garages.
Pondering on the worst case scenario here... :lol:

The worst case scenario would be if Dennis moved WNW, at Cat 4 strength, and it hit the area just west of Slidell. The area from Slidell east to Pascagoula would be devastated by the surge from the GOM, and the area around New Orleans would be devastated by the surge from Lake Pontchartrain.

On the other hand, looking at my atlas, another "worst case scenario" would be if Dennis moved just west of New Orleans. The strongest winds would move over New Orleans, but more importantly, surge from the south would as well. (if you look at an atlas, the GOM isn't that far from New Orleans). And, of course, the Slidell/Bay St. Louis/Biloxi/Gulfport area would still be inundated.

If Dennis hit the Pensicola area, it would just add to the devastation in that area already. If it hit Mobile, the surge from Mobile Bay would devastate the area.


The best area to make landfall would be near the rural marshes of central Louisiana, Kenedy County TX (not likely), or the rural "Big Bend" area of Florida (around Perry/Taylor County FL). The latter area has a special bonus: waters are a bit cooler there; just look at the SSTs.