Thursday, September 11, 2008

Latest excerpts from the NHC on Ike


BULLETIN
HURRICANE IKE ADVISORY NUMBER 41
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL092008
400 AM CDT THU SEP 11 2008
...LARGE HURRICANE IKE CONTINUES WEST-NORTHWESTWARD OVER THE
EAST-CENTRAL GULF OF MEXICO...

AT 4 AM CDT...0900 UTC...
THE TROPICAL STORM WARNING ALONG THE NORTHERN GULF
OF MEXICO COAST IS EXTENDED NORTHWARD AND EASTWARD TO
THE MISSISSIPPI
-ALABAMA BORDE
R...INCLUDING THE CITY OF NEW ORLEANS
AND LAKE PONTCHARTRAIN. A TROPICAL STORM WARNING IS NOW IN EFFECT
FROM THE MISSISSIPPI-ALABAMA BORDER WESTWARD TO EAST OF CAMERON
LOUISIANA. A TROPICAL STORM WARNING MEANS THAT TROPICAL STORM
CONDITIONS ARE EXPECTED WITHIN THE WARNING AREA WITHIN THE NEXT 24
HOURS.

A HURRICANE WATCH REMAINS IN EFFECT FROM CAMERON LOUISIANA WESTWARD
TO PORT MANSFIELD TEXAS. A HURRICANE WATCH MEANS THAT HURRICANE
CONDITIONS ARE POSSIBLE WITHIN THE WATCH AREA...GENERALLY WITHIN 36
HOURS.


THE 400 AM CDT POSITION...25.2 N...87.6 W. MOVEMENT
TOWARD...WEST-NORTHWEST NEAR 9 MPH. MAXIMUM SUSTAINED
WINDS...100 MPH.
MINIMUM CENTRAL
PRESSURE...946 MB.

---

HURRICANE IKE DISCUSSION NUMBER 41
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL092008
500 AM EDT THU SEP 11 2008

IKE CONTINUES TO EXHIBIT SOME
UNUSUAL STRUCTURAL CHARACTERISTICS.
DROPSONDE AND FLIGHT-LEVEL WIND DATA INDICATE THAT THE INTENSITY IS
STILL NEAR
85 KT...WHICH IS ANOMALOUSLY LOW FOR THE REPORTED
CENTRAL PRESSURE
. THE LATTER VALUE...946 MB...WOULD NORMALLY
CORRESPOND TO A BORDERLINE CATEGORY 3/4 HURRICANE
. THE TROPICAL
CYCLONE HAS A
VERY LARGE WIND FIELD...PARTICULARLY OVER THE
NORTHERN SEMICIRCLE AS OBSERVED BY BUOYS AND SHIPS OVER THE
NORTHERN GULF. HOWEVER IT CONTINUES TO HAVE A SMALL INNER CORE
WITH AN
EYE JUST UNDER 10 N MI IN DIAMETER. THERE HAS BEEN A
DOUBLE WIND MAXIMUM...ALTHOUGH HURRICANE HUNTER OBSERVATIONS

DYNAMICAL MODELS PREDICT THAT THE PORTION
OF THE RIDGE OVER TEXAS WILL WEAKEN IN ABOUT 48 HOURS AND THIS
WOULD CAUSE IKE TO TURN TO THE NORTHWEST AND NORTH. THERE
CONTINUES TO BE SOME DISAGREEMENT AMONG THE MODELS AS TO HOW SOON
AND HOW SHARP OF A TURN WILL OCCUR. HOWEVER...THE CONSENSUS OF OUR
MOST RELIABLE TRACK FORECAST MODELS IS UNCHANGED FROM THE PREVIOUS
ADVISORY. THEREFORE I HAVE MADE ESSENTIALLY NO CHANGES TO
THE OFFICIAL
TRACK FORECAST. THIS IS BETWEEN THE LATEST HWRF
RUN...WHICH
IS TO THE LEFT OF THE OFFICIAL FORECAST...AND THE
LATEST GFDL
RUN....WHICH IS TO THE RIGHT
. SUGGEST THAT THE OUTER WIND BAND IS
BEGINNING TO CONTRACT.


---

No comments: