HPC comparing it to 1944
Posted by cypresstx on 8/23/2011, 6:18 pm
also mentions the earthquake

http://www.hpc.ncep.noaa.gov/discussions/hpcdiscussions.php?disc=pmdepd

EXTENDED FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
336 PM EDT TUE AUG 23 2011

VALID 12Z FRI AUG 26 2011 - 12Z TUE AUG 30 2011


...HURRICANE IRENE TO STRONGLY AFFECT MUCH OF THE EASTERN SEABOARD
THIS WEEKEND...


PRELIMINARY UPDATE:

ON A LARGER SCALE MODELS SHOW GOOD AGREEMENT THROUGH THE MEDIUM
RANGE PERIOD WITH MAINTAINING AN UPPER VORTEX NEAR HUDSON BAY AND
AN UPPER HIGH OVER THE S. PLAINS...WITH VERY PROGRESSIVE FLOW
BETWEEN THAT HELPS TO SUSTAIN A MEAN EAST COAST TROUGH ONCE
INDIVIDUAL DISTURBANCES EXIT CENTRAL CANADA. ASIDE FROM HURRICANE
IRENE...DAY-TO-DAY SOLUTION DIFFERENCES ARE RELATIVELY SMALL AS
WELL AT LEAST UNTIL LATE IN THE PERIOD. THE LATEST NHC FORECAST IS
BETWEEN THE 00Z UKMET/ECMWF SOLUTIONS...WITH THE 00Z GFS SLIGHTLY
FASTER UNTIL ABOUT DAY 6/MON WHEN THE GFS IS CLOSET. THUS...DUE TO
THE SIGNIFICANCE OF IRENE WILL LIKELY USE THESE 3 MODELS THE MOST
IN CONSTRUCTING THE PRELIMINARY PRESSURES/FRONTS FOR THE MEDIUM
RANGE PERIOD. EVEN WITH RELATIVELY CLOSE DYNAMICAL TRACK GUIDANCE
TO IMPLEMENT IN THE UPCOMING PROGS...NO SOLUTION OTHER THAN THE
00Z ECMWF IS EVEN REMOTELY CLOSE TO THE HURRICANE MODEL GUIDANCE
CENTRAL PRESSURES SUCH AS THE GHM/HWRF WHICH HAVE IRENE BOTTOMING
OUT AROUND 930 MB AND SHIFTING TO THE LEFT OF THE OFFICIAL NHC
TRACK ALONG THE SOUTH CAROLINA COAST. HOWEVER...WHEN CONSIDERING
THE ENTIRE SOLUTION SPREAD JUST BY DAY 4/SAT...TRACK DIFFERENCES
SPAN ABOUT 300 NM...SO THERE REMAINS MUCH TO RESOLVE FOR THE
SENSIBLE WEATHER DETAILS OF IRENE. FOR NOW...WILL INTERPOLATE
BETWEEN THE LATEST NHC POINTS FOR DAYS 3 AND 4 WHICH HAS IRENE
MAKING LANDFALL BETWEEN MYRTLE BEACH SC AND WILMINGTON NC LATE
SATURDAY. REFER TO THE NHC FOR THE OFFICIAL TRACK AND INTENSITY
FORECAST.

ELSEWHERE...THE 00Z GFS AND ECMWF ARE QUITE CLOSE WITH THE TIMING
AND STRENGTH OF A SIGNIFICANT SHORTWAVE TROUGH AMPLIFYING IN THE
LEE OF THE CANADIAN ROCKIES ON DAY 5/SUN WITH AN ACCOMPANYING COLD
FRONTAL PASSAGE...AND ON DAY 6/MON WITH A SECONDARY SHORTWAVE
TROUGH BEGINNING TO INFLUENCE THE PACIFIC NORTHWEST.

WILL GREATLY REFINE THE INTERACTION BETWEEN IRENE AND THE MAIN
BAND OF WESTERLIES WITH THE ADVENT OF THE 15Z/23 NHC FORECAST AND
THE 17Z/23 COORDINATION CALL FOR THE FINAL ISSUANCE THIS
AFTERNOON.

...AFTERNOON FINALS...
PROG PRODUCTION AND PMDEPD INTERUPTED BY EAST COAST EARTHQUAKE AND
BUILDING EVACUATION.
IRENE TRACK ADJUSTED TO LATEST NHC GUIDANCE/FORECAST. LATEST AFTN
GLOBAL MODEL BEGINNING TO CONVERGE ON SOLUTION TRACK WITH RIGHT
MODELS CMC/GFS COMING LEFT AND ECMWF/UKMET COMING RIGHT. NHC TRACK
SHIFTED EASTWARD. AT THIS TIME THIS HAS ALL THE LOOK OF A VERY
DEEP DANGEROUS HURRICANE WITH  TRACK AND POSSIBLE INTENSITY TO
THAT OF THE GREAT HURRICANE OF 1944. SEE NHC
FORECAST/WATCHS/WARNINGS ALONG WITH NWS LOCAL OFFICE
WARNINGS/STATEMENTS.    
K JAMES/J CISCO/ F ROSENSTEIN

http://www.wunderground.com/hurricane/at19447.asp

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storm track shift?? - fire57mark, 8/23/2011, 5:12 pm
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