Ida takes aim at the U.S. Gulf Coast

By: Dr. Jeff Masters , 11:17 PM GMT on November 08, 2009

Share this Blog
1
+

Hurricane Ida burst into the Gulf of Mexico as a Category 2 hurricane with 100 mph winds this afternoon, and is poised to deliver a solid blow to the U.S. Gulf Coast between Southeast Louisiana and the Florida Panhandle on Tuesday morning. Radar imagery out of Cancun reveals that Ida has retained its tight inner core this afternoon, with only limited rain bands affecting Mexico and western Cuba. Top winds at Cancun, Mexico today were only 15 mph, despite the fact that Ida passed just 60 miles east of the city. Infrared and visible satellite loops show little change in the intensity of Ida's heavy thunderstorms this afternoon, but the cloud pattern is beginning to become distorted due to strong upper-level winds from the southwest that are creating 20 - 25 knots of wind shear over the hurricane. Water vapor satellite imagery reveals a large area of dry air to the southwest of Ida, but this dry air has not yet intruded into Ida's core. The latest 5:30 pm EST vortex report from the Hurricane Hunters showed that the central pressure had risen 1 mb, to 977 mb, but that the surface winds were still near 100 mph. They noted that the eyewall was open to the east, a sign that Ida's inner core may be in trouble.


Figure 1. MODIS satellite image from NASA's Terra spacecraft, taken at 1:35 pm EST 11/08/09. Image credit: NASA.

The intensity forecast for Ida
The high wind shear of 20 - 25 knots currently affecting Ida is forecast to persist at that level until Monday night. With the storm now beginning to show a distortion of the cloud pattern due to this shear, it would not be a surprise of the shear managed to inject some dry air into Ida's core Monday morning, significantly weakening the storm. Aiding this process will be cooler waters. Early Monday morning, Ida will be crossing over waters of 26°C, which is barely enough to support a hurricane. By Monday night, wind shear is expected to increase to 40 knots, which ordinarily would begin to tear the storm apart. This wind shear is due to an extratropical low pressure system over the western Gulf of Mexico, and this low will begin dumping cold, stable air into Ida Monday night through Tuesday. This will cause Ida to begin transitioning to an extratropical storm, and it is possible that during the transition Ida's winds will die down relatively slowly, despite the wind shear. The intensity forecast has a high amount of uncertainty, and I wouldn't be surprised at a landfall strength anywhere in the range of 45 mph - 80 mph. My personal best guess is a 50 - 60 mph tropical storm at landfall. Regardless of Ida's strength at landfall, the storm will be able to dump 4 - 8 inches of rain along the Gulf Coast, from New Orleans to Panama City. Isolated tornadoes will also be possible, primarily to the right side of Ida's track.


Figure 2. Maximum storm surge (depth of water above ground) for a Category 1 hurricane with 85 mph winds moving north-northeast at 15 mph. Ida is expected to be moving at this speed and direction at landfall, but will probably be weaker, so surges will not be this high. Image credit: NOAA SLOSH model run for Mobile Bay, 2008 version. Heights are given relative to the NAVD88 datum.

The storm surge forecast for Ida
Storm surge is the other major concern for Ida. With a strong high pressure system anchored over the U.S. today, the pressure difference between this high and Ida is creating a strong pressure gradient that will drive tides 3 - 5 feet above normal from New Orleans to the Florida Panhandle tonight. As Ida approaches on Monday, an additional rise in water will occur, and a large stretch of coast will be subject to very high water levels for an extended period of time. With battering waves building Monday afternoon into Tuesday morning, a significant coastal erosion event is shaping up. A particular concern is the western end of Alabama's Dauphin Island, where storm surges from four hurricanes over the past fifteen years have caused heavy damage to the low-lying heavily developed island. If Ida makes a direct hit on Mobile Bay as a Category 1 hurricane with 85 mph winds, a storm surge of up to six feet is possible there, assuming the storm hits at mean tide. The tidal range along the Gulf Coast varies by about 1.5 feet between low and high tide (Figure 3). High tide is near 2 am EST on Tuesday, but the official NHC forecast currently has the storm hitting between 6 am - 9 am, when the tide will be going out, so the storm may indeed be hitting at about mean tide.


Figure 3. The tide forecast for the Gulf Coast calls for high tide to occur around 2 am EST Tuesday morning. Ida is expected to hit later that morning, while the tide is going out.

I'll have an update Monday morning.

Links to follow:

U.S. Severe Weather Page
Cancun radar

Jeff Masters

Reader Comments

Comments will take a few seconds to appear.

Post Your Comments

Please sign in to post comments.

or Join

Not only will you be able to leave comments on this blog, but you'll also have the ability to upload and share your photos in our Wunder Photos section.

Display: 0, 50, 100, 200 Sort: Newest First - Order Posted

Viewing: 1341 - 1291

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38Blog Index

Quoting xcool:
mm nw ????? good jog west?

do you think it will regain strength in the morning? has it been down graded yet? why is it losing strength and is it going to continue to weaken?
Member Since: Posts: Comments:
Well new advisory says 105 mph.. I guess looks can be deceiving, maybe Ida is just keeping it's strength and not strengthening or weakening.. I expect a category 1 by morning, it looks ugly; however, the whole picture is setting up to be one huge dynamic low tomorrow, just look at the IR and see how the clouds are gathering from both storms? Florida peninsula will be effected with rain squalls and possibility of isolated tornadoes.
Member Since: Posts: Comments:
only time will tell with any luck it will stay on its path so no one else wakes up to a surprise
Member Since: July 17, 2005 Posts: 12 Comments: 793
1338. xcool
mm nw ????? good jog west?
Member Since: September 26, 2009 Posts: 2 Comments: 15684
yeah she is losing her punch... though even faster than what I expected.. I thought this could be anywhere from 70-85mph @ landfall..if the pressure rises more..it will be around 60mph @ landfall. The turn to the north will happen in a few hours (sunrise) then NNE by afternoon.
Member Since: Posts: Comments:
1336. Patrap
Member Since: July 3, 2005 Posts: 426 Comments: 128874
Dry air is saying chomp chomp chomp mmmmm Ida you were good. :)
Member Since: Posts: Comments:
WOW....from nearly a Cat 3 hurricane to a rapidly disentegrating xtrop wannabe storm in less than 12 hours. That's what wind shear, marginal SST's strong westerlies, and upper level troughs in November can do in the Gulf of Mexico.

Ida might even stay on the NNW course and flirt with NOLA, but even if it did, by the time it reached MoMiss (Mouth of the Mississippi) it will be at best a mid-level tropical storm, and more than likely it will be a NW Gulf gale center merging with the trough and getting pulled NE or E.

And it's still more likely that the trough will come early and pull everything NE into the mid FL Panhandle after all.

And what do you think will happen when it gets near the coast and encounters even cooler SST's of nearly 69-70 degrees??

Sorry, Tacoman and y'all, but climatology and reality beat wishcasting any old day. Prepare for the worst, and be ready for any surprises...but this is looking more and more like a early "Sou'easter" gale for the Northern Gulf after all.

It was fun while it lasted, though.


Anthony
Member Since: Posts: Comments:
1333. Patrap
Quoting mahep1911:
Patrap those models seem very clusterd on landfall in western florida and soaking the whole panhandle would you agree with that ? and what are your thoughts on intensity ?



I believe intensity has peaked,Leveled off,and will wane slowly.
But as to track,hard to say..she still making Longitude west as she goes N to NNW at 14
Member Since: July 3, 2005 Posts: 426 Comments: 128874
1332. Patrap
IDA Floater - Rainbow Color Infrared Loop
Member Since: July 3, 2005 Posts: 426 Comments: 128874
Quoting Patrap:


Minutes west translate to Miles NW now.
Going to be a close run though.

This things coming this way quick the longer it stays on this path and the faster it goes, i believe we will be seeing higher than what was previously expected..high trop. storm force
Member Since: Posts: Comments:
Patrap those models seem very clusterd on landfall in western florida and soaking the whole panhandle would you agree with that ? and what are your thoughts on intensity ?
Member Since: July 17, 2005 Posts: 12 Comments: 793
1329. Patrap
Quoting weatherman874:


Pat, i really think this thing is coming closer than there saying..school is canceled for alot of SE LA


Minutes west translate to Miles NW now.
Going to be a close run though.
Member Since: July 3, 2005 Posts: 426 Comments: 128874
Quoting Patrap:
06Z
Statistical/Simple Models (CLIPER,BAMs,LBAR,other Statistical Models)



Pat, i really think this thing is coming closer than there saying..school is canceled for alot of SE LA
Member Since: Posts: Comments:
Quoting silverstripes:


Here ya go

Link


Thanks!
Member Since: Posts: Comments:
Winds have picked up now in Pcola.
Member Since: Posts: Comments:
1325. Patrap
06Z
Statistical/Simple Models (CLIPER,BAMs,LBAR,other Statistical Models)




06Z
Dymamic Models (More sophisticated models)



Member Since: July 3, 2005 Posts: 426 Comments: 128874
Quoting Patrap:

Hmmmmmm.....
Member Since: Posts: Comments:
Member Since: Posts: Comments:
Quoting HellaGoose:
What is the link to see the HH info as it comes in?? thanks!


Here ya go

Link
Member Since: Posts: Comments:
I have to say what a tease! All the anticipation...
Very glad it's weakening though. Did not want a huge surge!
Member Since: Posts: Comments:
Member Since: Posts: Comments:
cooler waters...even though they may be 80dg.. its less than 86 in the NW carribean!
Member Since: Posts: Comments:
991mb ouch!!! Going down quickly
Member Since: Posts: Comments:
in S Florida,,only affects you will have is nothing!.. now in 3 days you might get showers..but thats nothing more than anything anytime of year.
Member Since: Posts: Comments:
1311. Yep...Appears to be TS Ida now based on the readings so far. Like I said earlier there may be a wind barb or 2 somewhere out there at Cat 1 strength but she is definitely a borderline strong TS/Cat 1. Expect a downgrade coming at the next advisory.
Member Since: Posts: Comments:
keep them coming bobby nothing else going on in here so somthing to look at would be nice lol
Member Since: July 17, 2005 Posts: 12 Comments: 793
so folks i am on the southeast coast of florida just above miami am i right that i will have no affect from Ida not even after her turn if she turns
Member Since: Posts: Comments:
1313. Patrap
Member Since: July 3, 2005 Posts: 426 Comments: 128874
Ida is still blowing up some deep convection around her center. Although her SW side is rapidly diminishing and it may not be too long before her LLC becomes partially exposed.
Member Since: Posts: Comments:
Hmmm.
000
URNT12 KNHC 090610
VORTEX DATA MESSAGE AL112009
A. 09/05:33:50Z
B. 24 deg 23 min N
087 deg 27 min W
C. 700 mb 3037 m
D. 60 kt
E. 298 deg 6 nm
F. 179 deg 63 kt
G. 084 deg 14 nm
H. 991 mb
I. 13 C / 3057 m
J. 16 C / 3038 m
K. 3 C / NA
L. NA
M. NA
N. 1345 / 7
O. 0.02 / 3 nm
P. AF304 0611A IDA OB 05
MAX FL WIND 63 KT E QUAD 05:27:00Z
MAX FL TEMP 18C 6NM FROM FL CNTR
MIN SLP 988MB 6NM FROM FL CNTR
;
In here, Ida is already a tropical storm with winds of 70 mph.
Member Since: Posts: Comments:
What is the link to see the HH info as it comes in?? thanks!
Member Since: Posts: Comments:
I need to sleep...tomorrow will be a long day. Can't make myself stop hitting refresh though! Guess it just looks like it's moving so fast now, don't want to wake up in 6 hrs with Ida knocking on my door earlier than expected.
Member Since: Posts: Comments:
I'm out for the night... have fun


Blog Update
Member Since: Posts: Comments:
lol leo

Yea I have to go in on duty tomorrow now well today a guess it is lol but it will be a busy 24 to 48 hours I hope every one is ready and no matter where she makes landfall she is going to turn east and drop lots of rain every where
Member Since: July 17, 2005 Posts: 12 Comments: 793
Ida is definately heading more west
Member Since: Posts: Comments:
WHO DAT?!? Nothin' like a hurricane party AND a Saints victory here in NOLA!

Can't remember who answered me the other day about the NOLA cruise ship leaving today for Mexico and beyond, but thanks for the replies. It did indeed take off as scheduled; not sure how they changed their route, though.

Thanks again!
Member Since: Posts: Comments:
Quoting mahep1911:
Ok now the Tallahassee weather office has their site updated. It looks like a 5 year old got ahold of the markers and went crazy lol is there any one else here still ?


I am, but probably not for too long... I think my worry-wart went to sleep! I'm amazed!
Member Since: Posts: Comments:
1303. lilith
Quoting atmoaggie:
I am mostly sure Ida will make landfall between Brownsville (TX) and Tampa. And has a good chance of counter-clockwise winds surrounding her center.


Are you sure about that? :-)
Member Since: Posts: Comments:
Good night everyone hopefully the threat is diminishing. There was a model yesterday or today that hooked the storm back s.w. to the bay of Campeche. Last look coldest cloud top looked to be doing something like that but to tired to watch anymore, would laugh is something like that happened.
Member Since: Posts: Comments:
Ok now the Tallahassee weather office has their site updated. It looks like a 5 year old got ahold of the markers and went crazy lol is there any one else here still ?
Member Since: July 17, 2005 Posts: 12 Comments: 793
Quoting Orcasystems:


I would love to take credit for it, but I can't... I found it on a joke page... with no authors name...so I just turned it into a webpage... seems to be a fitting page for the Blog some nights :)


Hehe... so true!

Well, the breezes are picking up, should be interesting tomorrow.
Member Since: Posts: Comments:

Ida has been the most interesting storm in a long time.
She helped me to stay at my computer and work all weekend. I hope the flooding at landfall and from surge is not too bad.
Sorry for the folks in El Salvador.
Take care and goodnight.
Member Since: Posts: Comments:
Yeah the MLC and LLC have separated. Extratropical transition has begun. See ya Ida. The NHC will end up nailing another one.
Member Since: Posts: Comments:
Quoting animalrsq:
TampaSpin, Thanks for all your input today. I'm in Citrus County, FL and am well prepared and keeping my eyes open even though it still looks like a Pensacola hit. I'm not discounting that easterly turn.



Your welcome....im no professional and would never confess to be...i just post what i see while giving a different prospective and possiblity that might occur. Guess i see something different and been wrong many times before and more to come....
Member Since: Posts: Comments:
1296. Patrap
...IDA HEADED NORTH-NORTHWEST TOWARD THE GULF COAST...

12:00 AM CST Mon Nov 9

Location: 24.4°N 87.5°W
Max sustained: 105 mph
Moving: NNW at 15 mph
Min pressure: 987 mb

Member Since: July 3, 2005 Posts: 426 Comments: 128874
Quoting LeopardMoth:


I love that, Orca!! So funny!


I would love to take credit for it, but I can't... I found it on a joke page... with no authors name...so I just turned it into a webpage... seems to be a fitting page for the Blog some nights :)
Member Since: Posts: Comments:
The dropsonde came back at 991 mb so expect that to be the new reported pressure.
Member Since: Posts: Comments:
...SUMMARY OF 1200 AM CST INFORMATION...
LOCATION...24.4N 87.5W
MAXIMUM SUSTAINED WINDS...105 MPH
PRESENT MOVEMENT...NORTH-NORTHWEST OR 345 DEGREES AT 15 MPH
MINIMUM CENTRAL PRESSURE...987 MB
Member Since: July 17, 2005 Posts: 12 Comments: 793
1am advisory still at 105mph

no vortex message yet though; so the weakening if there is some will be shown on the next advisory
Member Since: Posts: Comments:
1291. Patrap
Member Since: July 3, 2005 Posts: 426 Comments: 128874

Viewing: 1341 - 1291

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38Blog Index

Top of Page

About

Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.