Monday, August 30, 2010

Major (Category 4) Hurricane Earl Effecting the Virgin Islands & Puerto Rico Update 2

ZCZC MIATCDAT2 ALL
TTAA00 KNHC DDHHMM
HURRICANE EARL DISCUSSION NUMBER  22
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL072010
500 PM AST MON AUG 30 2010
 
THE RECONNAISSANCE AIRCRAFT MEASURED 116 KT FLIGHT-LEVEL WINDS AND
108 KT SFMR SURFACE WINDS SHORTLY AFTER 1500 UTC.  THIS WAS THE
BASIS FOR THE EARLIER INCREASE IN INTENSITY.  SINCE THAT TIME...THE
PRESSURE HAS CONTINUED TO DROP AND WAS DOWN TO 955 MB ON THE LAST
DROPSONDE RELEASED IN THE EYE AROUND 1700 UTC.  SINCE THE AIRCRAFT
DEPARTED EARL...THE EYE HAS CONTINUED TO CLEAR AND IS SURROUNDED BY
CLOUD TOPS TO -70 DEGREES CELSIUS OR COLDER.  OBJECTIVE SATELLITE
INTENSITY ESTIMATES HAVE INCREASED TO JUST ABOVE 6.0 ON THE DVORAK
SCALE AND SUPPORT AN INITIAL INTENSITY OF 115 KT...CATEGORY FOUR ON
THE SAFFIR-SIMPSON HURRICANE WIND SCALE.
 
EARL IS EXPECTED TO REMAIN IN A LOW SHEAR ENVIRONMENT AND OVER WARM
WATER DURING THE NEXT FEW DAYS AND SOME ADDITIONAL STRENGTHENING IS
LIKELY IN THE SHORT TERM.  THEREAFTER...EYEWALL CYCLES WILL LIKELY
INDUCE SOME FLUCTUATIONS IN INTENSITY...WHICH ARE DIFFICULT TO
PREDICT.  THE NHC FORECAST IS AGAIN NEAR THE HIGH END OF THE
INTENSITY GUIDANCE. AT DAYS 4 AND 5...THE HURRICANE IS FORECAST TO
MOVE OVER COOLER WATER AND INTO AN AREA OF INCREASING SHEAR WHICH
SHOULD RESULT IN WEAKENING.
 
THE INITIAL MOTION IS 290/13.  THE FORECAST REASONING REMAINS
UNCHANGED AS EARL IS EXPECTED TO TURN NORTHWESTWARD IN ABOUT 24
HOURS AROUND THE WESTERN PERIPHERY OF THE SUBTROPICAL RIDGE. THE
TRACK GUIDANCE HAS SHIFTED NOTICEABLY WESTWARD DURING THE FIRST
48 HOURS...WITH THE GFS AND ECMWF ON THE EASTERN EDGE OF THE
ENVELOPE.  THE OFFICIAL FORECAST HAS BEEN ADJUSTED WESTWARD...
PRIMARILY THROUGH 72 HOURS...AND LIES BETWEEN THE GFS/ECMWF AND THE
MULTI-MODEL CONSENSUS.
  
THIS IS A GOOD TIME TO REMIND EVERYONE THAT NHC AVERAGE TRACK
FORECAST ERRORS ARE 200 TO 300 MILES AT DAYS 4 AND 5.  GIVEN THIS
UNCERTAINTY...IT IS TOO SOON TO DETERMINE WHAT PORTION OF THE U.S.
EAST COAST MIGHT SEE DIRECT IMPACTS FROM EARL.
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      30/2100Z 19.3N  64.7W   115 KT
 12HR VT     31/0600Z 20.2N  66.3W   125 KT
 24HR VT     31/1800Z 21.7N  68.1W   130 KT
 36HR VT     01/0600Z 23.4N  70.1W   130 KT
 48HR VT     01/1800Z 25.8N  72.1W   125 KT
 72HR VT     02/1800Z 31.6N  74.7W   115 KT
 96HR VT     03/1800Z 38.0N  71.0W    95 KT
120HR VT     04/1800Z 45.5N  63.0W    70 KT...INLAND
 
$$
FORECASTER BROWN
 
NNNN
 
ZCZC MIATCPAT2 ALL
TTAA00 KNHC DDHHMM
BULLETIN
HURRICANE EARL ADVISORY NUMBER  22
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL     AL072010
500 PM AST MON AUG 30 2010
 
...EARL BECOMES A CATEGORY FOUR HURRICANE...MOVING AWAY FROM THE
VIRGIN ISLANDS...
 
 
SUMMARY OF 500 PM AST...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...19.3N 64.7W
ABOUT 110 MI...180 KM NE OF SAN JUAN PUERTO RICO
MAXIMUM SUSTAINED WINDS...135 MPH...215 KM/HR
PRESENT MOVEMENT...WNW OR 290 DEGREES AT 15 MPH...24 KM/HR
MINIMUM CENTRAL PRESSURE...948 MB...27.99 INCHES
 
 
WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY...
 
THE GOVERNMENT OF THE BAHAMAS HAS ISSUED A TROPICAL STORM WARNING
FOR THE TURKS AND CAICOS ISLANDS...AND A TROPICAL STORM WATCH FOR
THE SOUTHEASTERN BAHAMAS.
 
THE GOVERNMENT OF ANTIGUA AND BARBUDA HAS REPLACED THE HURRICANE
WARNING FOR THE BRITISH VIRGIN ISLANDS WITH A TROPICAL STORM
WARNING..AND DISCONTINUED THE TROPICAL STORM WARNING FOR ANGUILLA.
 
THE GOVERNMENT OF THE NETHERLANDS ANTILLES HAS DISCONTINUED THE
HURRICANE WARNING FOR ST. MAARTEN...SABA...AND ST. EUSTATIUS.
 
THE GOVERNMENT OF FRANCE WILL DISCONTINUE THE HURRICANE WARNING FOR
SAINT MARTIN AND SAINT BARTHELEMY AT 600 PM AST...2200 UTC.
 
THE HURRICANE WATCH FOR PUERTO RICO HAS BEEN DISCONTINUED...AND THE
HURRICANE WARNING FOR THE U.S. VIRGIN ISLANDS...CULEBRA...AND
VIEQUES HAS BEEN CHANGED TO A TROPICAL STORM WARNING.
 
SUMMARY OF WATCHES AND WARNINGS IN EFFECT...
 
A TROPICAL STORM WARNING IS IN EFFECT FOR...
* PUERTO RICO...INCLUDING THE ISLANDS OF CULEBRA AND VIEQUES
* U.S. VIRGIN ISLANDS
* BRITISH VIRGIN ISLANDS
* TURKS AND CAICOS ISLANDS
 
A TROPICAL STORM WATCH IS IN EFFECT FOR...
* SOUTHEASTERN BAHAMAS
 
FOR STORM INFORMATION SPECIFIC TO PUERTO RICO AND THE U.S. VIRGIN
ISLANDS...INCLUDING POSSIBLE INLAND WATCHES AND WARNINGS...PLEASE
MONITOR PRODUCTS ISSUED BY THE SAN JUAN NATIONAL WEATHER SERVICE
FORECAST OFFICE. FOR STORM INFORMATION SPECIFIC TO YOUR AREA OUTSIDE
THE UNITED STATES...PLEASE MONITOR PRODUCTS ISSUED BY YOUR NATIONAL
METEOROLOGICAL SERVICE.
  
 
DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
AT 500 PM AST...2100 UTC...THE CENTER OF HURRICANE EARL WAS LOCATED
NEAR LATITUDE 19.3 NORTH...LONGITUDE 64.7 WEST.  EARL IS MOVING
TOWARD THE WEST-NORTHWEST NEAR 15 MPH...24 KM/HR.  THIS GENERAL
MOTION IS EXPECTED TO CONTINUE TONIGHT...FOLLOWED BY A TURN TOWARD
THE NORTHWEST ON TUESDAY.  ON THE FORECAST TRACK...THE CENTER OF
EARL WILL MOVE AWAY FROM THE VIRGIN ISLANDS TONIGHT AND PASS EAST
OF THE TURKS AND CAICOS ISLANDS ON TUESDAY NIGHT AND WEDNESDAY.
 
MAXIMUM SUSTAINED WINDS HAVE INCREASED TO NEAR 135 MPH...215
KM/HR...WITH HIGHER GUSTS.  EARL IS A CATEGORY FOUR HURRICANE ON
THE SAFFIR-SIMPSON HURRICANE WIND SCALE.  SOME ADDITIONAL
STRENGTHENING IS FORECAST DURING THE NEXT DAY OR SO.  
 
HURRICANE FORCE WINDS EXTEND OUTWARD UP TO 70 MILES...110 KM...FROM
THE CENTER...AND TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 200
MILES...325 KM.
 
ESTIMATED MINIMUM CENTRAL PRESSURE IS 948 MB...27.99 INCHES.
 
 
HAZARDS AFFECTING LAND
----------------------
WIND...TROPICAL STORM CONDITIONS WILL GRADUALLY SUBSIDE OVER THE 
BRITISH AND U.S. VIRGIN ISLANDS TONIGHT.  TROPICAL STORM CONDITIONS
ARE EXPECTED OVER PORTIONS OF PUERTO RICO THROUGH TONIGHT. STRONGER
WINDS...ESPECIALLY IN GUSTS...ARE LIKELY OVER ELEVATED TERRAIN IN
PUERTO RICO.  TROPICAL STORM CONDITIONS ARE EXPECTED TO BEGIN TO
SPREAD INTO THE TURKS AND CAICOS ISLANDS TUESDAY AFTERNOON.
 
STORM SURGE...STORM SURGE WILL RAISE WATER LEVELS BY AS MUCH AS 3 TO
5 FEET ABOVE GROUND LEVEL PRIMARILY NEAR THE COAST IN AREAS OF
ONSHORE WIND OVER THE BRITISH VIRGIN ISLANDS...AND 1 TO 3 FEET
ELSEWHERE IN THE WARNING AREA.  THE SURGE WILL BE ACCOMPANIED BY
LARGE AND DANGEROUS BATTERING WAVES.
 
RAINFALL...EARL IS EXPECTED TO PRODUCE TOTAL RAINFALL ACCUMULATIONS
OF 4 TO 8 INCHES OVER THE NORTHERN LEEWARD ISLANDS...THE VIRGIN
ISLANDS AND PUERTO RICO...WITH POSSIBLE ISOLATED MAXIMUM AMOUNTS OF
12 INCHES...ESPECIALLY OVER HIGHER ELEVATIONS. THESE RAINS COULD
CAUSE LIFE-THREATENING FLASH FLOODS AND MUDSLIDES.
 
 
NEXT ADVISORY
-------------
NEXT INTERMEDIATE ADVISORIES...700 PM AST AND 900 PM AST.
NEXT COMPLETE ADVISORY...1100 PM AST.
 
$$
FORECASTER BROWN/PASCH
 
NNNN

0 Comments:

Post a Comment

<< Home