Hurricane Isaac

[stevofunnelcl]

All this talk of Cat 2's and Cat 4's. I'd imagine the media are going into over-hype mode over there

I'm a cynic, Isaac has never gotten very well organised, so unless it does develop a vertically stacked inner core, i think

it's possible this storm may not make it to Hurricane status

There was talk of dry air still affecting the storm on the recent discussion i read from NHC

It could still happen, i'll probably look like a fool later on, but that's what i think at the moment

Nightmare to forecast, i accept that. Large uncertanties regards intensity and final landfall at the moment

[Iceberg]

You could be Right Stevo, the 12z models will be interesting again as they will have a lot of upper air data from the NOAA flights.

ATM Isaac is looking quite good, radar shows very good banding and precip has started to explode up around the centre as it slowly moves away from Cuba.

I think now Isaac is vertically stacked, it's just lacking the precip due to the dry air caused by land interaction to intensify.

[summer blizzard]

Shockingly the BBC even have this on the news so certainly some interest around it.

The fact that pressure dropped immediately offshore makes me bullish coupled with expected slowing, the next 12 hours may see it reorganise but i expect it to start bombing afterward.

[knocker]

At 1300z.

[Gray-Wolf]

I get the feeling someone might of 'Fish'ed ' me when Isaac was a mere storm and I'd seen a model run place it over N.O.? (LOL)

When they thread the needle through the Key's and Cuba I'm always a tad concerned as to do that feat it places it on a path that ,allowing for the northern jog, runs it into that coast. When the GOM is undisturbed by previous storms there is a lot of energy to pump the 'cane up to a major in no time at all.

[Iceberg]

quite busy today but the 06z's from hwrf, gfdl and gfs all agree on a New Orleans hit heres the GFS, intensity is a Major 100-115kts at this range of forecast.

Also the CDO is forming readily again and an eye wall looks like it might be forming on radar...

[lfcdude]

what category would it be if this hits new Orleans? cat 4 i100-115kts?. Katrina esk?

Edited August 26, 2012 by lfcdude

[Iceberg]

Yep might be similar to katrina, but its a way off yet, the potential is certainly there.

From latest 4.00pm nhc update. They have also moved the track westwards a bit and its put New Orleans and LA in the cone.

"VISIBLE SATELLITE AND IMAGERY SUGGEST THAT THE TROPICAL CYCLONE IS

GRADUALLY BECOMING BETTER ORGANIZED. THERE ARE INDICATIONS OF

INNER CORE DEVELOPMENT WITH INCREASED CONVECTION NEAR AND OVER THE

CENTER...AND A PARTIAL EYEWALL IS IN EVIDENCE ON RADAR IMAGERY. THE

BANDING FEATURES HAVE BECOME MORE DISTINCT OVER THE NORTHERN AND

EASTERN SEMICIRCLES OF THE CIRCULATION. "

[toggerob]

Isaac moving through 4000kj of CAPE currently. not too shabby,

[summer blizzard]

Organising rather rapidly now, satellite is significantly better than a few hours ago.

Ever more convinced - look for a 30-40mb pressure drop over monday and tuesday,

[evil monkey]

Would I be right in thinking that Issac could now interact with the Gulf Loop Current?

[Iceberg]

30 plus all the way now, recon found a large 996-997 centre, however radar shows a much smaller centre forming with the eyewall maybe 80% complete, once done with the convection over the top we could see a drop to 980 pretty quick and a hurricane.

[knocker]

The NAM certainly isn't looking for anything extreme. Whether it's handling this well awaits to be seen.

[Evening thunder]

Wonder what it would feel like to be in one of these storms, might be quite odd to us Brits temp wise as for example 'Sombrero Key' has both the temp and the dew point on 28C, with a 47mph sustained wind:

http://windmapper.com/FL/observations

[Iceberg]

isaac is still getting the wrap around of the eye done, inflow is starting in the south, outflow etc very good.

12z models are pretty similar, gfs and hwrf in the middle going for a new orleans hit, (both cat 4, hwrf 120kts), ecm slight east, gfdl slightly west near the texas border.

All in All pretty much as before.

key west has falling pressure now 998.4mb and falling still.

[Chris D]

Yes, I think when the structure is fully developed, which it pretty much is nearly, RI is a given with the SST's (although TC Heat Potential isn't that high).

I have suspected a Gulf coast hit ever since it entered the Caribbean, and for once I'm right! However, it's for the worse as this looks likely to cause major problems. Hoping people will see sense and get out.

Edited August 26, 2012 by Chris D

[Iceberg]

Recon just found pressure of 992.8mb so pressure is definately falling now, at a pronounced rate.

[knocker]

The 1500z surface chart and 1800z plots,

[lottiekent]

Looking very wet across the Florida Keys as TS Isaac passes over:

http://www.a1aweather.com/florida-keys.php

[Iceberg]

Key west down to 996.8mb and still falling. He is really going some.

Parts of neworleans have a red alert and tourists are being advised to leave.

[toggerob]

Wonder what it would feel like to be in one of these storms, might be quite odd to us Brits temp wise as for example 'Sombrero Key' has both the temp and the dew point on 28C, with a 47mph sustained wind:

http://windmapper.com/FL/observations

I would liken it to the classic 'hairdryer' quote, the closest the UK has been in terms of actual effects from a Tropical Storm system was ex-Irene last year, I remember standing on the nearby hill with 50mph+ gusts battering me constantly and yet this wind was tropical in nature and didn't even require a coat to stand in.

The only difference between then and a Hurricane for proper is the fact Hurricane's are more destructive barocentric wise in terms of the storm surge and +100mph consistent wind, outside of the gusts.

[geoffw]

is the NHC being over cautious with their latest forecast wind intensity?

[summer blizzard]

I would liken it to the classic 'hairdryer' quote, the closest the UK has been in terms of actual effects from a Tropical Storm system was ex-Irene last year, I remember standing on the nearby hill with 50mph+ gusts battering me constantly and yet this wind was tropical in nature and didn't even require a coat to stand in.

The only difference between then and a Hurricane for proper is the fact Hurricane's are more destructive barocentric wise in terms of the storm surge and +100mph consistent wind, outside of the gusts.

Yeh, the main difference is that even our worst storms never give sustained winds above TS strength whilst Wilma for example has 185mb and gusts over 200mph (unimaginable).

[East_England_Stormchaser91]

NHC seem to be placing Isaac to hit New Orleans slap bang on. This is getting interesting now. Lets pray that them levees do the job this time.

[summer blizzard]

is the NHC being over cautious with their latest forecast wind intensity?

Almost certainly in my opinion, pressure has dropped 5mb in the past 6 hours (wind often lags) and the picture shows it is about to pop an eye.

My big worry with this is that NO is going to be flattened, Katrina was weakening at landfall and speeding up while this will be slowing and strengthening, on top of that this TS already has TS winds approaching 250 miles outside the centre (bigger than a lot of hurricanes) and so with slow speed the storm surge from this will be immense.

Sub 960mb and a strong category 3 is my opinion for the moment, but i am tending ever more aggressive.

Issac is also left of the NHC track.

With precip like below, RI is practically a given (black)..