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Hurricane DORA (Text)

ZCZC MIATCDEP4 ALL
TTAA00 KNHC DDHHMM
 
HURRICANE DORA DISCUSSION NUMBER  16
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP042011
200 AM PDT FRI JUL 22 2011
 
STRONG VERTICAL SHEAR CONTINUES TO TAKE ITS TOLL ON HURRICANE DORA
THIS MORNING.  WHAT WAS ONCE...JUST A FEW HOURS AGO...A WARM EYE
SURROUNDED BY QUITE COLD CLOUD TOPS IS NOW A PARTIALLY EXPOSED
LOW-LEVEL VORTEX WITH THE DEEP CONVECTION TO BE FOUND ONLY IN THE
SOUTHERN SEMICIRCLE.  RAW DATA-T NUMBERS FROM TAFB...SAB...AND ADT
HAVE ALL PLUMMETED.  ASSUMING THAT IT TAKES SOME LAG TIME FOR THE
WINDS TO WEAKEN AS MUCH AS THE CONVECTIVE SIGNATURE...THE INTENSITY
IS ANALYZED AT 90 KT...20 KT WEAKER THAN THE PREVIOUS ADVISORY.
 
WHILE THE STRONG NORTHERLY VERTICAL SHEAR SHOULD DIMINISH OVER THE
NEXT DAY...DORA WILL BE ENCOUNTERING AN INCREASINGLY HOSTILE
THERMODYNAMIC ENVIRONMENT WITH COLD SSTS AND A STABLE ATMOSPHERE
WITHIN THE NEXT 24 HOURS.  WITHIN ABOUT TWO DAYS...THE CYCLONE WILL
BE TRAVERSING OVER 23C WATER AND MOVING THROUGH AN ATMOSPHERE THAT
WILL LIKELY NOT ALLOW DEEP CONVECTION.  THE INTENSITY FORECAST IS
CLOSE TO THE LGEM-SHIPS STATISTICAL INTENSITY MODELS...BUT
SUBSTANTIALLY BELOW THAT OF THE PREVIOUS ADVISORY BECAUSE OF THE
CONTINUED RAPID WEAKENING.
 
THE HURRICANE IS MOVING NORTHWESTWARD AT 8 KT ALONG THE SOUTHWESTERN
PERIPHERY OF A DEEP-LAYERED RIDGE.  THIS SAME FEATURE SHOULD
CONTINUE STEERING DORA NORTHWESTWARD AT ABOUT THE SAME SPEED UNTIL
DISSIPATION.  THE FORECAST TRACK IS BASED UPON A BLEND OF THE
MULTI-MODEL CONSENSUS IS NEARLY THE SAME AS THE PREVIOUS ADVISORY.
 
IN ADDITION TO THE WEAKENING...AMSU AND ASCAT SATELLITE PASSES
INDICATE THAT DORA EXHIBITS A SUBSTANTIALLY SMALLER 34-KT WIND
RADII THAN PREVIOUSLY ANALYZED.  THIS SUGGESTS A DIMINISHED RISK OF
TROPICAL-STORM-FORCE WINDS FOR SOUTHERN BAJA CALIFORNIA AS SHOWN IN
THE REDUCED WIND SPEED PROBABILITIES.
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  22/0900Z 18.9N 108.8W   90 KT 105 MPH
 12H  22/1800Z 19.5N 109.5W   75 KT  85 MPH
 24H  23/0600Z 20.5N 110.6W   60 KT  70 MPH
 36H  23/1800Z 21.4N 111.7W   50 KT  60 MPH
 48H  24/0600Z 22.5N 113.0W   40 KT  45 MPH
 72H  25/0600Z 24.5N 116.0W   30 KT  35 MPH...POST-TROP/REMNT LOW
 96H  26/0600Z 26.0N 117.5W   25 KT  30 MPH...POST-TROP/REMNT LOW
120H  27/0600Z 27.0N 118.0W   20 KT  25 MPH...POST-TROP/REMNT LOW
 
$$
FORECASTER LANDSEA/STEWART
 
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