ALERT: Hurricane Isidore forecasted to have at least 150 MPH winds within 72 hours

[newsperson999]

Statement as of 5:00 PM EDT on September 21, 2002

Air Force recon data indicate major Hurricane Isidore has continued to rapidly strengthen and the central pressure has dropped 21 mb in the past 13 hours. A pressure of 946 mb generally corresponds to a maximum wind of about 117 kt. However...the eye is open to the west and there may be a lag in the wind field. Also...dropsonde data indicated about 105 kt surface winds...but winds just a few hundred above the surface have been as high as 130 kt. The three satellite agencies reported a Dvorak satellite intensity estimate of t6.0...or 115 kt...while the 3-hour objective Dvorak T-number was also t6.0. Based on this information...the initial intensity was increased to 110 kt.

The initial motion estimate is 270/3. Recon fix positons since about 12z indicate Isidore has actually remained nearly stationary the past 6 hours...but right over some of the hottest water in the Atlantic Basin. Steering currents remain weak and are forecast by all of the global to remain weak or even get weaker. Isidore remains caught between a mid- to upper-level low east of Florida and one to the west over the Bay of Campeche. A weak and narrow low- to mid-level ridge extends across the northern Gulf of Mexico coast from Florida westward to Texas. Given the relative weakness of this ridge...only 5880 meters at 500 mb...it would not take much of a shortwave trough to erode it and allow Isidore to drift slowly poleward. All of the NHC model guidance...except LBAR...keeps Isidore moving on a slow west or west-southwest track through the forecast period. The AVN and GFDL are very similar in hooking Isidore to the southwest around the western Yucatan Peninsula in 36 to 48 hours. This may be some artifact of terrain interaction which I have ignored for this advisory package since all of the global models show no significant ridging north of isiodre to push the system to southwest. The forecast calls for a slow...less than 6 kt...motion throughout the forecast period with a slight west-northwestward motion after 48 hours as a strong shortwave trough drops down the west side of the broad longwave trough...which is expected to erode the weak ridge over Texas and the northwest Gulf of Mexico and allow Isidore to gain some latitude. However... the slower Isidore moves during the next 36 to 48 hours will determine just how far north and the cyclone will move in the longer time periods beyond 72 hours. The good news is that it appears that Isidore is not going to go anywhere fast. The bad news is that it will remain over very hot water.

The central pressure has dropped 21 mb in the past 13 hours. A typical rapid intensification period. This trend would normally continue for another 12 hours or so...but radar and recon data indicate that the eye is open to the west and that an eyewall replacement cycle may be starting. As such...the official intensity forecast is held below the ships intensity model which brings Isidore to 135 kt in 36 hours and 140 kt in 60 hours. This type of intensification is certainly possible given the low shear...less than 6 kt...and high SSTs...about 30c/86f. However...predicting internal convective changes is nealry impossible so there could be flucuations by as much 10 kt either way from the offical intensity forecast. Some coastal upwelling may weaken the hurricane slightly as it moves west of 88w longitude...but then some restrengtnening is forecast after 48 hours when Isidore is forecast to move back over warmer water.

Forecaster Stewart

forecast positions and Max winds

initial 21/2100z 21.9n 86.2w 110 kts
12hr VT 22/0600z 21.9n 87.0w 120 kts
24hr VT 22/1800z 21.9n 88.0w 125 kts
36hr VT 23/0600z 21.9n 89.2w 125 kts
48hr VT 23/1800z 22.0n 90.3w 125 kts
72hr VT 24/1800z 22.5n 92.5w 130 kts

[Fiddlstix]

Bump

[newsperson999]

my guess winds 140..pressure 940 mb at 1am advisory..CAT 4.it doesn't get much better than this(this may be the last Sat shot for a while..the past few nights the Sat went down at this time.. eclipse)

CLICK HERE

[willyone]

How did you reach that conclusion? Some of the biggest storms have been in Oct. As long as the water is warm Hurricanes are possible.

[Dog Gone]

Do houseboats have an internet connection?

[Dog Gone]

Clicking there results in an interesting message.

[newsperson999]

ok..click HERE than click on the storm for a close up

[newsperson999]

Another good shot here

[eastforker]

Satelite or wireless will get you there,I am realy excited.Wife and I don't make alot of money to afford the big dollar boats but this one is way underpriced.We might sell the land locked house and go for the dream of adventure.

[Tex_GOP_Cruz]

I may be wrong, but US NOAA weather satellites are in geosync orbit and don't really eclipse for long periods. The sats take two mains types of images -- infrared and visual. The IR gives temperature. High clouds mean more development; these show up as cooler clouds, being higher. IR images can be taken 24 hours a day if I recall correctly. The visual satellite provides better structural information but is always "lost" some time after dusk (fades out after sunset, fades in before sunrise) because the ground is no longer sufficiently bright. That's why the 315Z time is the time of the last image -- that's 10:15 CDT or about when even the western part of the sat footprint becomes too dark to be useful.

[Dog Gone]

Whoa. I didn't get what you meant at first, but when I did click on the first image your link called up, it zoomed right into the storm.

It looks like a bad night to be visiting the ruins at Chichen Itza!

[jamaly]

People were found drowned in their attics after Hurricane Betsy, because places went from having no water to having 20 feet of water in 15 minutes," Krieger said

Preceding Hurricane Georges one of the New Orleans meteorologists recommended that people keep axes handy so they could chop their way out of their attics, if necessary. My family had already evacuated by this time, a friend later told me that statement was what convinced her to evacuate.

[eastforker]

I could live in margaritaville and still vote a sraight republican ticket.When you retire you should be able to relive your youth yet make the peons foot the bill ,don't ya think,hell,politicians do it,why shouldn't the common folk?

[Dog Gone]

Good for you! Just don't get crazy and take it out into the Gulf of Mexico. ;-)

[Joe Hadenuf]

150 mile per hour winds? Isn't that just a breeze in Texas?

[eastforker]

Well, you can, just gotta watch the weather reports.

[NELSON111]

NOAA GOES sats eclipse during this time of year. They are blocked from the sun's light and since they run on Solar power...don't have the energy to run the instruments to they are shut off. It lasts for 48 days each cycle and is greatest (3 hours or so) near the equinox. We are at this point so expect an outage of about 3 hours tonight.

[Tex_GOP_Cruz]

>NOAA GOES sats eclipse during this time of year. They are blocked from the sun's light and since they run on Solar power...don't have the energy to run the instruments to they are shut off. It lasts for 48 days each cycle and is greatest (3 hours or so) near the equinox. We are at this point so expect an outage of about 3 hours tonight.

Looks like I stand corrected. Thanks for the piece of info. With the sun "near" the equator at the equinox it makes sense that even something as high as geosync would eclipse near local midnight. Duh!

[Ditter]

My grandfather survived the !900 Galveston storm. He waid the water was more than 2 feet deep in the upstairs of the building he was in. If he had been in the attic of a one story house he would have been drowned. Gulp, & I wouldn't be here.

[dennis1x]

sure looks like it now, but i dont think they will up the wind to 140 without aircraft confirmation and im not sure if they fly this time of night.

big jog to the south the last hour or two, if any more than a wobble could spell doom for Isidore....i think things are starting to look questionable as to the future of the storm...the NHC seemed to bring up some question in the last advisory concerning a more southerly track.

if it jogs 50 miles to the south it could be over land for a prolonged time.

[Ditter]

Sounds like you guys are gearing up for a real fun time. ;9}