Hurricane Isaac

[phw115wvwx]

Bold prediction here: I believe we'll have Hurricane Isaac between the 11pm - 5am advisories given how things are trending tonight.

Isaac needs more time than you think, Tavores.  It has not developed a persistent inner core yet, and the wind field is rather large for a tropical storm.  You want to see a tightening up of that wind field and the development of an inner core, which would become the inner eyewall once it is a hurricane, to achieve overall intensification.  Furthermore, the inflow for Isaac in the southeast quadrant has been disrupted for the past few days by the mountains in Cuba.  It will do better once the inflow is further away from land.

[toxictwister00]

Bold prediction here: I believe we'll have Hurricane Isaac between the 11pm - 5am advisories given how things are trending tonight.

Isaac needs more time than you think, Tavores.  It has not developed a persistent inner core yet, and the wind field is rather large for a tropical storm.  You want to see a tightening up of that wind field and the development of an inner core, which would become the inner eyewall once it is a hurricane, to achieve overall intensification.  Furthermore, the inflow for Isaac in the southeast quadrant has been disrupted for the past few days by the mountains in Cuba.  It will do better once the inflow is further away from land.

I know Patrick, I wasn't really all that serious about it. I know large storms take an enormously long time to consolidate an eye, just look at how long this thing has been a tropical storm! Over a week I know, that's gotta be some kind of a record. Oh and speaking of an eye...about halfway there on this microwave image.

[toxictwister00]

We might have our hurricane at 5pm...

Product: Air Force Vortex Message (URNT12 KNHC)
Transmitted: 27th day of the month at 20:23Z
Corrected: This observation corrected a previous observation.
Aircraft: Air Force Aircraft (Last 3 digits of the tail number are 306)
Storm Number & Year: 09L in 2012
Storm Name: Isaac (flight in the North Atlantic basin)
Mission Number: 27
Observation Number: 10
A. Time of Center Fix: 27th day of the month at 19:30:40Z
B. Center Fix Coordinates: 26°14'N 85°56'W (26.2333N 85.9333W) (View map)
B. Center Fix Location: 245 miles (394 km) to the WSW (241°) from Tampa, FL, USA.
C. Minimum Height at Standard Level: 1,280m (4,199ft) at 850mb
D. Estimated (by SFMR or visually) Maximum Surface Wind: 43kts (~ 49.5mph)
E. Location of the Estimated Maximum Surface Wind: 11 nautical miles (13 statute miles) to the NNE (12°) of center fix
F. Maximum Flight Level Wind Inbound: From 100° at 54kts (From the E at ~ 62.1mph)
G. Location of Maximum Flight Level Wind Inbound: 19 nautical miles (22 statute miles) to the NNE (19°) of center fix
H. Minimum Sea Level Pressure: 982mb (29.00 inHg)
I. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 20°C (68°F) at a pressure alt. of 1,543m (5,062ft)
J. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 22°C (72°F) at a pressure alt. of 1,544m (5,066ft)
K. Dewpoint Temp & Sea Surface Temp (collected at same location as temp inside eye): Not Available
L. Eye Character: Open in the north
M. Eye Shape & Diameter: Circular with a diameter of 20 nautical miles (23 statute miles)
N. Fix Determined By: Penetration, Radar, Wind, Pressure and Temperature
N. Fix Level: 850mb
O. Navigation Fix Accuracy: 0.02 nautical miles
O. Meteorological Accuracy: 1 nautical mile
Remarks Section:
Maximum Wind Outbound: 74kts (~ 85.2mph) in the southwest quadrant at 19:52:30Z
Maximum Flight Level Wind: 74kts (~ 85.2mph) in the southwest quadrant at 19:52:30Z


CLOSE, but no cigar, winds up to 70 mph, pressure continues to drop down to 981mb and is now moving NW at 12 mph per 5pm advisory. NHC is once again forecasting a Cat. 2 hurricane (100mph) by landfall.

[phw115wvwx]

The key is seeing the pressure dropping.  Pressure is always the first variable to respond during intensification.  The winds will respond later, so I expect Isaac to become a hurricane tonight.  It's not looking good for New Orleans, LA and Biloxi, MS.  Hopefully, Isaac won't bring near the impacts that Katrina did in these areas exactly 7 years ago.

[toxictwister00]

Notice the convection firing up from the NW, N, and NE sides. It's truly amazing how this thing has taken on a different shape every evening over the past week. Looks more like a textbook tropical cyclone than it ever has in it's entire lifetime.

http://www.ssec.wisc.edu/data/1min/index.php?action=view_animation&req_method=nframes_enddate&enddate=20120827&endtime=2054&nframes=100&band=1&res=4&aniwidth=1280&aniheight=1024

[stormymikala]

Hi everyone!Tropical Storm Issac gave some nice breezy, rainy weather for me in Fort Myers.I took some pics of the storm.

[toxictwister00]

Starting to burst convection around the northern part of the center. It'll be interesting to see what we have over the next 10-15 hours. It might be me, but it looks like Isaac is shedding some of his skin that band that was covering up a large part of FL/southern GA seems to be detaching itself away from Isaac condensing it's size.

[Localonthe8s]

What's the wind speed for the storm right now?

[toxictwister00]

What's the wind speed for the storm right now?

Still 70mph with a 981mb pressure. RECON is out investigating right now. We could have a Cat 1 hurricane within anytime over the next 12-15 hours or so.

11PM UPDATE - ISAAC'S WINDS REMAIN AT 70 MPH, PRESSURE DROPS TO 979MB!

[Pop Light Brown]

That dry air is something else, isn't it? The pressure has been falling for much of the day, but the winds have yet to catch up thanks to that dry air. I think we'll have a 75-85 mph hurricane tomorrow.

Some people evacuated from across the region, but most have been raiding the stores and are staying put.

Oh, and most of the New Orleans TV stations have gone to around-the-clock coverage.

[Pop Light Brown]

Hopefully this shows up well. Isaac's impacts from NWS New Orleans.

(if all the graphics don't show, go here: http://www.srh.noaa.gov/lix/

[toxictwister00]

"Eye" See You Isaac.

[toxictwister00]

Given the reports coming in from RECON as of late, I feel 99.9% positive we have at least a 75 mph hurricane. I just don't see how we don't.

EDIT: 12:20PM ET - 11 AM ADVISORY UPDATED; SPECIAL ADVISORY ISSUED; ISAAC NOW A CATEGORY ONE HURRICANE. (75 mph)Surface Winds of 66kts and Flight level winds over 90kts being reported

[phw115wvwx]

Isaac is now officially a hurricane.  It literally crossed over the threshold just after the 11 AM EDT advisory.  We shouldn't be worried so much about the terminology here between a 70 mph tropical storm and a 75 mph hurricane as flooding and storm surge are going to be the major issues, not winds.  Here's a part of the summary statement:

LOCATION...28.1N 88.6W
ABOUT 75 MI SSE OF THE MOUTH OF THE MISSISSIPPI RIVER
ABOUT 160 MI SE OF NEW ORLEANS LOUISIANA
MAXIMUM SUSTAINED WINDS...75 MPH
PRESENT MOVEMENT...NW AT 10 MPH
MINIMUM CENTRAL PRESSURE...975 MB

Anyone in LA and the lower Mississippi River valley needs to be ready for major flooding problems over the next couple days.

[toxictwister00]

Isaac attempting to build an eyewall: TAKE TWO.

http://www.ssd.noaa.gov/goes/east/gmex/flash-rb.html

I thought about this today, well the past couple of days. Is there a chance Isaac will cause upwelling the longer it sits out there in the gulf?