09/20/05: FCST Hurricane Rita

[Michael P. Morris]

From the latest NHC discussion (11 pm EDT) it seems that the forecast center has little faith in the ETA's ejection of the cutoff low presnetly off the southern California coastline. Fromt he water vapor imagery it appears that the low has come ashore a bit further south than the model had anticipated, which could cause it to remain cutoff for a bit longer instead of becoming absorbed in the general flow as a shortwave skirting the central plains. This would lead to a weakening of the ridge currently in place and more of a southeasterly to SSEly steering flow as Rita enters the Gulf.

It is interesting to note that the NHC has put great faith in the FSU Superensemble after its extremely accurate handling of Katrina.

 

[Anthony Silver]

NHC QUOTE:

...RITA BECOMES FIFTH MAJOR HURRICANE OF THE 2005 SEASON AS IT MOVES
WESTWARD AWAY FROM THE FLORIDA KEYS...

:shock: Rita is now a Cat 3...looks to be Cat 4 by this afternoon. Anyone willing to bet that it becomes Cat 5 shortly before landfall? Water temps are about 85.3 in the central Gulf and I wouldn't expect any shearing to occur, so this is not looking good at all for the ESE Texas coast.

 

[Glen Romine]

Seems to be some disagreement among the NHC forecasters this morning. Beven the conservative - and Avila going for broke. Seems Avila has great faith in the Dvorak intensity - despite Bevin noting the Key West radar didn't concur, and there hasn't been a recon flight since yesterday evening, about the time of the Dvorak intensity taking a nosedive.

http://cimss.ssec.wisc.edu/tropic/odt/RITAP.GIF

Will be interesting to see what the planes find once they get there. Noting that Rita is about to cross the warm loop current - but then will have a long trek across rather shallow warm waters - so peak intensity should occur in the next 24 hrs, and then expect a gradual weakening.

http://www.aoml.noaa.gov/phod/dataphod1/wo...005263god26.png

Glen

 

[Ryan McGinnis]

Judging from the donut IR satellite presentation and the fact what appears to be mesovortices are spinning around in the large eye on the RAMDIS vis floater, I'd say that Rita is transitioning to an annular hurricane. With it about to hit the loop current, I'd guess she's going to go through some truely historic deepening before slowly weakening before landfall. The only saving grace I can see right now is dry air in the western Gulf. It's unlikely for any of it to penetrate the storm given it's current presentation, but you never know; maybe it'll hit an ERC at an unopportune time and ingest some dryness.

I think, though, in 24 hours, the central pressure is going to be real eye-opening.

 

[Sam Sagnella]

The 00z SHIPS model, which was initialized at 150kts, shows only slight additional strengthening to 154kts in 12hrs. The 18z GFDL, which was initialized at 141kts, immediately weakened the hurricane to 120kts in 6hrs followed by continued slow weakening (obviously did not materialize), and has a landfall just SW of Galveston. It is interesting to note that the 00z MM5-AF has a SW Louisiana landfall, whereas the 18z run had it landfalling over Galveston Bay. While this drastic of a shift has not been noted in all models, the tracks have been inching up the coast run-by-run. As far as the intensity forecast is concerned, I have to side with the SHIPS solution of slight additional strengthening, though I still think it will max out at 160kts, with a slow weakening thereafter. Unfortunately, the worst-case scenario appears quite possible as far as Houston/Galveston are concerned; as of right now, I think it will landfall between Freeport and Galveston during the early morning hours of Saturday as a strong, but weakening category 4 (winds ~145mph). Surge heights in the vicinity of Galveston Bay could approach or exceed 20 feet.

**shivers**