ATL: ISAAC - Post-Tropical - Discussion

[northjaxpro]

If Isaac continues on a crawl basically, the flooding and surge issues will be enormous across LA, MS and AL coast.

Which is what happened in Florida and what people have been saying here all along if they read between all the uninformed posts about how the storm is a wimp because it doesn't have 300MPH winds. Flooding and surge are the issues here. With the angle of approach, this could push an unfortunate amount of water into the mouth of the Mississippi.

I totally agree with you WeatherGuesser. I always feared that Isaac would eventually slow to a crawl and get into a weaker steering envronment after rounding the periphery of the ridge. Apparently, that is happening and torrential rains and storm surge will really unfortunately be the big stories when all is said and done. I pray for all in the path of Isaac. Please take care and be safe everyone!

[Time_Zone]

Looks like it's finally become a hurricane

[TeamPlayersBlue]

Those high wind values are so far away from the center though.

[tolakram]

Java based rapid scan live loop: http://wwwghcc.msfc.nasa.gov/cgi-bin/ge ... umframes=5

1 minute flash based loop: http://www.ssec.wisc.edu/~rabin/goes14/loop_srso.html

Latest

[capepoint]

IMO Issac remains an unorganized mess this morning. When all is said and done, I doubt hurricane force sustained winds will be logged with the center landfall, which still looks to me to be near la/ms line. The main problems will be heavy rain and surge flooding. Also, of course will have some trees down and roof damage, like normal with high-end ts where stronger bands produce higher gusts. Lots of flooding damage though, people need to respect the amount of water that they are going to get. And remember the tornado threat.

Of course, I could be wrong........

Personal Forecast Disclaimer:
The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products.

[PTrackerLA]

Looks like some healthy convection exploding on the north side on the live 1 min loop. BTW can't say enough how cool this is to have this year!

[PTPatrick]

I suspect if this was in the Atlantic it would already be called a Cane ... I've seen cat 2 canes not look this good. Heck Ive seen piddly naked swirls that you wouldn't get out of bed for be called canes. I understand the reasoning. But not sure what's more important....science and the pursuit of being more accurate or making sure folks don't just see this any old tropical storm. No matter what the non S2K public generally doesn't understand there isn't much of difference between a weak cane and a strong TS. Not saying there is a right answer here...

[rtd2]

If Isaac continues on a crawl basically, the flooding and surge issues will be enormous across LA, MS and AL coast.

Which is what happened in Florida and what people have been saying here all along if they read between all the uninformed posts about how the storm is a wimp because it doesn't have 300MPH winds. Flooding and surge are the issues here. With the angle of approach, this could push an unfortunate amount of water into the mouth of the Mississippi.

I totally agree with you WeatherGuesser. I always feared that Isaac would eventually slow to a crawl and get into a weaker steering envronment after rounding the periphery of the ridge. Apparently, that is happening and torrential rains and storm surge will really unfortunately be the big stories when all is said and done. I pray for all in the path of Isaac. Please take care and be safe everyone!

Agreed!... infact local mets here now saying 12ft + storm surge in Hancock county, 10-12 ft around Biloxi,Gulfport and 8-10ft over and including alabama coast...

[Chris_in_Tampa]

NOAA HDOB 29 High Values
Flight (30s): 54 knots
Flight (10s): 55 knots
SFMR Surface (10s): 63 knots

[Sanibel]

977 & 99mph flight level wind translates to 72mph surface wind

[Chris_in_Tampa]

High Values AF HDOB 18
Flight (30s): 83 knots
Flight (10s): 83 knots
SFMR Surface (10s): 53 knots

[tolakram]

Saved 30 frame radar loop from New Orleans

DO NOT QUOTE THIS IMAGE

[wxwatcher1999]

Is the weakness to the north closing up causing isaac to slow down?

[wxman57]

968 and still a TS? thats almost a cat3 pressure. its unbelievable it can be at 28.60 and be a TS.

It's all about the orientation of the pressure gradient. Lacking an eyewall, the pressure gradient is spread out over a large distance. RMW is about 60nm now, so no tight center. Take a tornado with a 970mb pressure and it could produce winds of 150 mph. Spread that same gradient out over 100nm and you have a TS. Same amount of energy but the energy is not concentrated on a narrow path.

[MHurricanes]

Here is millibars table with comparisons to windspeed:

http://hypertextbook.com/facts/StephanieStern.shtml

From Joe Bastardi this morning:

Joe Bastardi ‏@BigJoeBastardi
HD wind obs are 80 g 86 kts pressure is 976 this supports 85-90mph storm. IS NHC trying to say if this were "Gordon" its not hurricane?

[rainstorm]

based on that radar its going to miss the mouth of the MI to the south.

[CYCLONE MIKE]

Latest rainbow loop looks pretty impressive. Isaac seems to finally be in the process of wrapping some heavier convection around the western and northern sides now. If he can keep this up with the slow movement could really ramp up.

[rainstorm]

968 and still a TS? thats almost a cat3 pressure. its unbelievable it can be at 28.60 and be a TS.

It's all about the orientation of the pressure gradient. Lacking an eyewall, the pressure gradient is spread out over a large distance. RMW is about 60nm now, so no tight center. Take a tornado with a 970mb pressure and it could produce winds of 150 mph. Spread that same gradient out over 100nm and you have a TS. Same amount of energy but the energy is not concentrated on a narrow path.

i understand what you are saying but if this comes inland at 976 or lower and they are still calling it a TS i bet it does high end cat1 damage.

[WilmingtonSandbar]

Saved 30 frame radar loop from New Orleans

DO NOT QUOTE THIS IMAGE
[ img]http://img528.imageshack.us/img528/5509/zzwunidsmap.gif[/img]

According to that radar, precipitation on the north side of the storm is lees than impressive.

[tolakram]

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