000
WTNT42 KNHC 152048
TCDAT2
TROPICAL STORM ANA DISCUSSION NUMBER 15
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022009
500 PM AST SAT AUG 15 2009
THE CENTER OF ANA CONTINUES TO BE EXPOSED TO THE WEST OF THE
CONVECTION BY MODERATE VERTICAL WIND SHEAR. THE UPPER-LEVEL WINDS
NEAR ANA ARE CURRENTLY LIGHT AND SOUTHERLY...MOST OF THE
CONTRIBUTION TO THE SHEAR SEEMS TO BE FROM THE FAST LOW-LEVEL FLOW
THE CENTER IS EMBEDDED IN. SATELLITE INTENSITY ESTIMATES FROM TAFB
AND SAB REMAIN 35 KT...AND THAT REMAINS THE INITIAL INTENSITY.
THE INITIAL MOTION IS 270/15. OVERALL...A LOW/MID-LEVEL RIDGE
SHOULD STEER ANA QUICKLY WESTWARD TO WEST-NORTHWESTWARD...WITH ALL
THE TRACK GUIDANCE AGREEING WITH THIS SCENARIO. HOWEVER...THERE
REMAINS A SIGNIFICANT SPREAD IN THE 120 HR FORECAST POINTS. THE
ECMWF AND BAMS ARE AT THE NORTHERN EXTREME...FORECASTING ANA TO
PASS OVER OR NEAR THE SOUTHERN FLORIDA PENINSULA BY 120 HR.
AT THE OTHER EXTREME ARE THE UKMET...GFDN...AND BAMM...WHICH
FORECAST ANA TO PASS SOUTH OF HISPANIOLA AND BE OVER THE
NORTHWESTERN CARIBBEAN AT 120 HR. THE NEW FORECAST TRACK IS AGAIN
SHIFTED SOUTHWARD FROM THE PREVIOUS TRACK IN BEST AGREEMENT WITH
THE NOGAPS. HOWEVER...THE NEW TRACK IS STILL ON THE NORTHERN SIDE
OF THE GUIDANCE ENVELOPE AND NOTABLY NORTH OF THE CONSENSUS MODELS.
IT IS UNCLEAR WHETHER THE CURRENT SHEAR IS A TEMPORARY TREND OR A
SIGN OF LONG-TERM TROUBLE FOR ANA. THE LARGE-SCALE MODELS SUGGEST
THE FORMER IS THE CASE...AND SO THE INTENSITY FORECAST CONTINUES TO
CALL FOR STRENGTHENING. HOWEVER...THE CYCLONE IS STILL SURROUNDED
BY DRY AIR IN WATER VAPOR IMAGERY...AND THE NEW FORECAST TRACK NOW
CALLS FOR THE SYSTEM TO MAKE LANDFALL ON HISPANIOLA...AN OCCURRENCE
THAT HAS DESTROYED STORMS MUCH STRONGER THAN ANA. THE INTENSITY
FORECAST ASSUMES THAT THE CIRCULATION WILL SURVIVE THIS PASSAGE AND
INTENSIFY OVER THE WATERS NORTH OF CUBA. AS BEFORE...THIS
INTENSITY FORECAST HAS GREATER THAN NORMAL UNCERTAINTY.
----------------
000
WTNT43 KNHC 152033
TCDAT3
TROPICAL STORM BILL DISCUSSION NUMBER 2
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL032009
500 PM AST SAT AUG 15 2009
SATELLITE IMAGERY INDICATES THAT THE DEPRESSION IN THE FAR EASTERN
ATLANTIC HAS CONTINUED TO BECOME BETTER ORGANIZED. THE CYCLONE IS
LARGE AND HAS NUMEROUS CYCLONICALLY-CURVED CONVECTIVE BANDS WITH
THE OUTFLOW PRIMARILY ON THE WESTERN SEMICIRCLE. DVORAK T-NUMBERS
HAVE INCREASED AND SUPPORT UPGRADING THE SYSTEM TO TROPICAL STORM
STATUS WITH AN INITIAL INTENSITY OF 35 KNOTS. BILL IS EXPECTED TO
REMAIN OVER WARM WATERS AND EMBEDDED WITHIN LIGHT SHEAR THROUGH THE
FORECAST PERIOD. STRENGTHENING IS INDICATED AND BILL IS EXPECTED TO
BECOME A HURRICANE IN 3 TO 4 DAYS. THIS IS CONSISTENT WITH THE
UPWARD INTENSITY TREND INDICATED BY THE GUIDANCE.
BILL IS IN THE DEEP TROPICS AND IS WELL-EMBEDDED WITHIN THE EASTERLY
TRADE WINDS. THE CYCLONE IS MOVING JUST SOUTH OF DUE WEST OR 265
DEGREES AT 14 KNOTS. IN GENERAL...NO SIGNIFICANT CHANGE IN THE
STEERING CURRENTS IS ANTICIPATED AND BILL SHOULD BEGIN TO TURN A
LITTLE MORE TO THE WEST-NORTHWEST AROUND THE PERIPHERY OF THE
SUBTROPICAL RIDGE IN A DAY OR SO...WITH LITTLE CHANGE IN FORWARD
SPEED. THERE HAS NOT BEEN A SIGNIFICANT CHANGE IN THE GUIDANCE...AND
THE BULK OF THE MODELS HAS BILL AS A HURRICANE JUST NORTH AND VERY
NEAR THE NORTHERN LEEWARD ISLANDS AND SO DOES THE OFFICIAL
FORECAST.
不好意思
一兩天前有注意到熱帶低壓(安娜)和擾動(比爾)沒錯
這幾天是夏季課程結束,秋季正規課程下周一開始
大概下一報就開始開工
NOAA有文章講過大西洋很平靜不代表不會有颶風災害
像上一次安德魯出現的1992年也很安靜
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MASTER ▎ ┌──┐ ERROR CODE: 0168
▎ │0168│ DEFINITION: Main memory overflowed, shut down
ALARM ▎ └──┘ the master bus sw required.
▂▂▂▂▎ ┌──┬──┬──┐
│ERR │SYS │COMM│
└──┴──┴──┘
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