CAT 5 Hurricane Dean - Archived threads

[tolakram]

Looks like a shot of dry air is getting in again.

[Cyclone1]

Looks like a shot of dry air is getting in again.

Now that dean is a well established hurricane, that shouldn't be a major hindrance for it.

[marcane_1973]

Is it just me or the center in the latest visible does not look as good. It seemed to look better a couple of hours ago when it looked like the eye was clearing out some. It also looks like a little dry air has been sucked in to the southwest and south of Dean.

[Sanibel]

Strengthening cyclones get that 'hazy' look like you see above.

I'm sure the people on Martinique aren't unaware of what is about to hit them. Looks like cycloneye, BVIgal OK now.

PS - It's not really "Dry air" per se but "dry-er air" than the pockets of moister air around it. In the tropics, in summer, the surface air above the Atlantic is plenty humid.

[BeaumontHorn]

pardon my ignorance being first post as I just found this board. And maybe I'm thinking too outside the box, but with all the high pressure and hot temps that were in Texas and now seem to be shifting east ward into LA, MS, AL, GA and Erin just going into south TX would all that moving to the east eventually set up for Dean to turn more north impacting upper TX coast?

[Windsurfer_NYC]

From nencweather

"GFDL shows a ridge with a southern periphery oriented more northwest to southeast than other models. The 06Z NOGAPS had shown a similar solution. In previous years, GFDL has shown excellent skill, particularly in 2005, in predicting the strength of the subtropical ridge compared to other models. However, when given a secondary ridge such as the scenario seen here, it has performed poorly, often showing a bias to the north due to underestimating the new high pressure strength. This was seen several times in 2004. With respect to this, the track will remain in the guidance envelope, and will only be shifted northward if significant evidence that the secondary high pressure will not be as strong as indicated. Otherwise, no other major steering currents will impact Dean, and there is little else to say except that the farther north Dean goes, the slower it will move because the ridge will be weaker. The track forecast is down the center of the guidance envelope and takes Dean into the Yucatan Peninsula by Day 5."

The GFDL has been modified and updated since 2004, so be careful when making assumptions that it'll perform the same way in 2007.

[SouthFloridawx]

I wouldn't worry about it too much... looks like it has a pretty large envelope of moisture developing.

http://tinyurl.com/ytg2t9

[Steve]

>>What concerns you most? Please tell me not the GFDL.

That's not concerning, it's ALARMING. But I hear what NENC Weather is saying. However, it's not just a "ridge" issue, it's the ridge coupled with what it anticipates the cutoff low forming out of that TUTT tomorrow night is going to do along with Dean's forward speed. It may be a blip in a bad model run. It may not. Any time there is a progged Cat 3 or Cat 4 heading toward the Gulf, all Gulf residents should be somewhat concerned. Ultimately, I think the GFDL is the outlier here. But should the UKMET or some of the generally non-southern biased models start to agree with a stallout of the cutoff ULL, Dean catching it, or whatever, then we're in a new ballgame.

I wouldn't make the call either way or any other way right now. I'm not that good.

Steve

[Derek Ortt]

Dean is looking fine, apepars to just be a minor fluctuation

The outflow is rapidly improving so this appears to still be intensifying

[Sabanic]

pardon my ignorance being first post as I just found this board. And maybe I'm thinking too outside the box, but with all the high pressure and hot temps that were in Texas and now seem to be shifting east ward into LA, MS, AL, GA and Erin just going into south TX would all that moving to the east eventually set up for Dean to turn more north impacting upper TX coast?

We have had above normal temps here for almost 2 weeks. If we get any warmer it will mean temps over 100 (105 yesterday), and heat indexes have already been steadily over 110

[Derek Ortt]

one major difference between Martinique and Grenada... Martinique has many times as many people as does Grenada

[btangy]

The only way that Dean will be able to turn NW faster is if the mid-latitude pattern becomes more progressive so that the ridge axis is further E or if Dean really trucks and catches up to the 500mb weakness. At this point, none of the global models indicate this will occur. The upper level low off the SE coast should slide off to the W pretty quickly.

[SouthFloridawx]

Dean is looking fine, apepars to just be a minor fluctuation
The outflow is rapidly improving so this appears to still be intensifying

Pretty cool looking system, eh Derek?

[Sabanic]

>>What concerns you most? Please tell me not the GFDL.

That's not concerning, it's ALARMING. But I hear what NENC Weather is saying. However, it's not just a "ridge" issue, it's the ridge coupled with what it anticipates the cutoff low forming out of that TUTT tomorrow night is going to do along with Dean's forward speed. It may be a blip in a bad model run. It may not. Any time there is a progged Cat 3 or Cat 4 heading toward the Gulf, all Gulf residents should be somewhat concerned. Ultimately, I think the GFDL is the outlier here. But should the UKMET or some of the generally non-southern biased models start to agree with a stallout of the cutoff ULL, Dean catching it, or whatever, then we're in a new ballgame.

I wouldn't make the call either way or any other way right now. I'm not that good.

Steve

Well stated Steve

[Steve]

>>The only way that Dean will be able to turn NW faster...or if Dean really trucks and catches up to the 500mb weakness. At this point, none of the global models indicate this will occur.

None but the GFDL. See the global models thread for exactly that scenario presented.

Steve

[Sanibel]

pardon my ignorance being first post as I just found this board. And maybe I'm thinking too outside the box, but with all the high pressure and hot temps that were in Texas and now seem to be shifting east ward into LA, MS, AL, GA and Erin just going into south TX would all that moving to the east eventually set up for Dean to turn more north impacting upper TX coast?

The US is in a zonal flow right now. This means the weather systems aren't snaking up and down in troughs and ridges with a serpentine jet stream but are instead flowing from west to east in a flat flow. The SE High can get under that and stay put or even drift slightly west. Get a hurricane under that and it will track straight west. I'm not saying it WILL do that, but it is possible to not recurve north.

[Emmett_Brown]

From nencweather

"GFDL shows a ridge with a southern periphery oriented more northwest to southeast than other models. The 06Z NOGAPS had shown a similar solution. In previous years, GFDL has shown excellent skill, particularly in 2005, in predicting the strength of the subtropical ridge compared to other models. However, when given a secondary ridge such as the scenario seen here, it has performed poorly, often showing a bias to the north due to underestimating the new high pressure strength. This was seen several times in 2004. With respect to this, the track will remain in the guidance envelope, and will only be shifted northward if significant evidence that the secondary high pressure will not be as strong as indicated. Otherwise, no other major steering currents will impact Dean, and there is little else to say except that the farther north Dean goes, the slower it will move because the ridge will be weaker. The track forecast is down the center of the guidance envelope and takes Dean into the Yucatan Peninsula by Day 5."

Do you happen to have a link... I would like to read future discussions. Thanks!

[HURAKAN]

pardon my ignorance being first post as I just found this board. And maybe I'm thinking too outside the box, but with all the high pressure and hot temps that were in Texas and now seem to be shifting east ward into LA, MS, AL, GA and Erin just going into south TX would all that moving to the east eventually set up for Dean to turn more north impacting upper TX coast?

WELCOME TO THE BOARD. IT WILL BE A VERY INTERESTING WEEK AHEAD.

Ultimately the combination between the high pressures and the trough of low pressure will decide where Dean will go. The Bermuda-Azores High has been pretty strong so far steering Dean mostly to the west. The trough is supposed to be weak which will be leave the door open for the highs to rule. It will be interesting entering next week how strong the high over the SE of the US is because that will decide if Dean continues west, or moves more to the WNW or NW.

[Wx_Warrior]

That was from nencweather, not from myself. I'm not that smart, hence the reference I put above it before I posted.

[SouthFloridawx]