Hurricane Isaac

[Pop Light Brown]

Looks like I may be boarding up windows early next week (hope not).

[TWCToday]

Looks like I may be boarding up windows early next week (hope not).

The Euro shifted east considerably and is actually in line with the GFS for the first time. I'd shoot for a landfall between Mobile and Pensacola based on those two.

Although the hurricane hunters are having a hard time finding a center where the NHC last depicted. Might be further south and west. That could throw a wrench in things.

I also wonder how bad the mountains in Cuba are going to gut Isaac.

[toxictwister00]

I did a little quick research on past storms that have had a similar path over Cuba/Southwestern Haiti as projected by the NHC and below are those storms and how strong they were post-Cuba making landfall in the Gulf. All of these storms went across some high elevations of Cuba or in fact tracked across a large portion of Cuba and were able to steadily or quickly recover in the Gulf. In addition, most of these storms occurred around the same time as Isaac and into the peak of Hurricane Season. Keep in mind, I'm not trying to suggest or predict Isaac will have the same fate as the ones listed below, I just felt it was an interesting food for thought. My overall point here is that even though Isaac could go over Cuba and scrape the Southern part of Haiti it doesn't necessarily mean it's out when it's down. It has a decent potential to recover quickly as long as it doesn't do anything wacky like sit and stall destroying what circulation is left once it's in the Gulf.

I was gonna post some honorable mentions, but my list would have been a lot longer.

Great Middle Florida Hurricane (August 16-27, 1851)
Category Three (US Landfall)
Major Hurricane 3 (September 8-18, 1875)
Category Three (US Landfall)
Hurricane 5 (September 1-13, 1878)
Category Two (US Landfall)
Indianola Hurricane (August 12-21, 1886)
Category Four (US Landfall)
Major Hurricane 4 (September 18-October 1, 1894)
Category One (US Landfall)
Great Galveston Hurricane (August 27-September 15, 1900)
Category Four (US Landfall)
Hurricane 2 (August 8-17, 1928)
Tropical Storm (US Landfall)
Major Hurricane Cleo (August 20 - September 5, 1964)
Category Two (US Landfall)
Major Hurricane Georges (September 15-October 1, 1998)
Category Two (US Landfall)

EDIT: In other news, Isaac may be finally starting to develop a vertically stacked circulation, RECON is finding peak flight level winds as strong as 62kts. or 71mph. Surface winds are coming in at 56 kts. We might see winds bumped up into the 55-65mph range come the 11am advisory.
Peak (10s) Flt. Lvl. Wind:    62 knots (~ 71.3 mph)   
SFMR Peak (10s) Sfc. Wind:    56 knots (~ 64.4 mph)

[phw115wvwx]

Isaac has finally slowed down to a forward speed of 14 mph, which has helped improve its organization.  The winds have increased to 60 mph.  If it can somehow stay just south of the mountains in Haiti and survive the trek through Cuba, then I would be ready to start calling out the Gulf Coast for landfall with certainty.

[toxictwister00]

ECMWF is NOT wavering from a Central Gulf (Mobile) hit from the 00z run last night. For verbatim, I'm sure it's showing a major, it bombs down to 963mb! That's two identical runs so far.

[toxictwister00]

8pm Update: Pressure continues to fall and forward motion has slowed down. Wind speeds remain at 65mph. Something tells me Isaac has a few tricks up his sleeves. 

Location: 17.3°N 72.0°W
Moving: NW at 10 mph
Min pressure: 992 mb
Max sustained: 65 mph

11pm Adivisory - Significant change to track, Isaac could possibly miss hitting most of Cuba! Strong Cat 1 hurricane expected at landfall. (90mph)
Location: 17.7°N 72.5°W
Moving: NW at 14 mph
Min pressure: 990 mb
Max sustained: 70 mph

[phw115wvwx]

After looking over all the models today, I'm ready to say that eastern LA, MS, AL, GA, and FL are in the line of fire for this storm.  I'm really worried about the areas in MS and AL that still haven't recovered completely from Katrina.  A hurricane watch and a tropical storm warning are now in effect for southern FL.  There's even a possibility that Isaac could mostly bypass Cuba to the north, which would make it a stronger storm approaching the Gulf.

Looking further ahead after landfall, Isaac may stall out over the Southeast, which would lead to major flooding problems.  A front over the Mid-Atlantic and surface high pressure over the Great Lakes may block it from advancing any further northward for a long while.  In short, all people in the areas mentioned above should start preparing now if they haven't done so already.  My red avatar being up at this point ought to give everyone a clue.

[toxictwister00]

This storm keeps surprising me with every advisory. 24 hours ago I would have never expected it to wind up like this. Dr. Greg Postel/Brian Norcross predicted the NHC would change their forecast cone into more of a "S Bend" shape around the northern periphery of Cuba heading into the Gulf. 

EDIT: Do I need to go to sleep or is that really an eye popping out?

[Trevor]

Watches/Warnings Update:
Hurricane Warning for the Florida Keys and SW Florida.
Hurricane Watch for the Miami area and Haiti
Tropical Storm Warning for Lake Okeechobee, portions of SE Florida, the Bahamas, the Dominican Republic, and the southern tip of Cuba
Tropical Storm Watch for portions of Western Florida, Central Cuba, and Jamaica.

*Bold indicates that the US is affected

[toxictwister00]

HPC has me getting 8-10 inches, I haven't seen that much rainfall at one time since the Great Flood of 2009 where we got about that much on September 21, 2009. That whole month alone was nothing but floods. Ironically that should be enough rainfall to erase our entire drought or at least the majority of it.

EDIT: 11am advisory - Nothing changed as far as it's strength or pressure, but it has increased in forward speed and the NHC is now calling for a Category Two Hurricane (100mph) surprised by that change. I wonder if the HWRF had any affect on that decision, it kept showing a major hurricane striking the Central Gulf.

11:00 AM EDT Sat Aug 25
Location: 20.1°N 74.6°W
Moving: NW at 17 mph
Min pressure: 998 mb
Max sustained: 60 mph

[TampaMillTWC88]

There is already effects of Isaac around Miami and in South Florida, and some outer bands could reach parts of the Bay Area by tonight.

[Zach]

Tropical storm watches are in effect for the Bay Area as well.

[Eric]

The Daytona Beach area is under a tropical storm watch... and my weather radio loudly informed me of that.  As I was trying to sleep.  I nearly crashed through the ceiling.

[toxictwister00]

There is already effects of Isaac around Miami and in South Florida, and some outer bands could reach parts of the Bay Area by tonight.

That's not from Isaac, that's from an upper low disturbance that's actually guiding Isaac NW. That disturbance will move to the WSW further into the Gulf so Isaac can begin to make his WNW turn towards the FL Keys over the next 24 hours.

I feel I should make notice of this, the models continue to not only strengthen (In a lot of cases bomb) Isaac. The 12z GFS today shows for verbatim a major hurricane striking west of Mobile, AL. What concerns me more is the models continue to slow Isaac down while it's in the Gulf approaching to make landfall, I don't have to tell you how much that's not a good thing. That gives it the opportunity to continue to strengthen which means if that happens, the NHC's forecast of 100mph could turn out to be a little conservative we'll see how things evolve over the next 24-72hours this will be Isaac's time to shine if he plans to.

[Trevor]

Look at the HWRF...holy crap. That would make this a Category 3 making landfall near Destin, FL. I bet, however, that this is completely different by tomorrow. At least intensity wise...HWRF is holding strong on the track.