000
AXNT20 KNHC 170537
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL  
205 AM EDT FRI JUN 17 2011

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL 
AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS
OF SOUTH AMERICA...AND ATLANTIC OCEAN TO THE AFRICAN COAST
FROM THE EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED
ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND 
METEOROLOGICAL ANALYSIS.

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0530 UTC.

...TROPICAL WAVES...

TROPICAL WAVE EXTENDS FROM 12N41W TO 3N46W MOVING W AT 10-15 KT. 
WAVE REMAINS EMBEDDED WITHIN A MOISTURE MAXIMUM AS INDICATED BY 
THE TOTAL PRECIPITABLE WATER IMAGERY. WAVE ALSO SHOWS A GOOD 
INVERTED-V STRUCTURE ON VISIBLE NIGHT CHANNEL. THE CONVECTION IS 
MOSTLY CONFINED TO THE ITCZ FROM 5N-11N BETWEEN 41W-55W.

TROPICAL WAVE IS MOVING ACROSS THE WESTERN CARIBBEAN ANALYZED 
FROM JAMAICA NEAR 18N77W TO THE NW COAST OF COLOMBIA NEAR 9N77W 
MOVING W AT 10-15 KT. THIS WAVE IS EMBEDDED IN A SURGE OF DEEP 
MOISTURE ON TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED MODERATE 
TO ISOLATED STRONG CONVECTION IS S OF 15N W OF 73W.   

...ITCZ/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS FROM INLAND ACROSS MAURITANIA IN WEST 
AFRICA...ENTERING THE ATLC NEAR 19N16W CONTINUING S TO 7N20W. 
THE ITCZ AXIS CONTINUES FORM THIS POINT ALONG 3N30W 2N40W 6N43W. 
THEN...IT RESUMES E OF A TROPICAL WAVE FROM 7N46W TO 5N52W. 
SCATTERED MODERATE TO STRONG CONVECTION MOVES OUT THE COAST OF 
SIERRA LEONE...GUINEA...AND NORTHERN LIBERIA E OF 20W FROM 
3N-10N. SIMILAR CONVECTION IS WITHIN 180 NM N OF THE ITCZ AXIS W 
OF 40W. 

...DISCUSSION...

GULF OF MEXICO...
WATER VAPOR IMAGERY CONTINUES TO SHOW VERY DRY AIR AND STRONG 
SUBSIDENCE ALOFT COVERING THE GULF OF MEXICO THIS EVENING. AT 
SURFACE...A 1015 MB HIGH REMAINS CENTERED NEAR 27N85W. THIS 
BENIGN FEATURE IS PRODUCING FAIR WEATHER ACROSS THE DISCUSSION 
AREA...WITH ONLY A FEW ISOLATED WEAK SHOWERS NOTICED OFF THE 
WESTERN COAST OF THE YUCATAN PENINSULA AND BAY OF CAMPECHE 
AND WESTERN WATERS OF CUBA INCLUDING THE YUCATAN CHANNEL S OF 
22N E OF 95W. OTHERWISE...A VERY RELAX PRESSURE GRADIENT IS 
OBSERVED ALMOST OVER THE ENTIRE BASIN...GENERATING 5-10 KT 
ANTICYCLONIC WINDS ACROSS THE AREA...GUSTING TO 20 KT WITHIN 90 
NM OFF THE TEXAS COAST. NO SIGNIFICANT CHANGES ARE EXPECTED 
DURING THE NEXT 24 HOURS AS THE SURFACE RIDGE DRIFTS TO THE NE 
OVER THE NEXT 24 HOURS. 

CARIBBEAN SEA...
THE WEATHER IN THE SW CARIBBEAN CONTINUES UNDER THE INFLUENCE 
OF THE MONSOON TROUGH THAT EXTENDS ACROSS CENTRAL AMERICA OVER 
COSTA RICA INTO NORTHERN COLOMBIA...AND A TROPICAL WAVE NE OF 
COLOMBIA. THE COMBINATION OF THESE TWO FEATURES IS GENERATING 
SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS S OF 15N W OF 73W. 
THE NORMAL EASTERLY TRADES HAVE BEEN REPLACED FOR BROAD CYCLONIC 
TURNING AROUND THE CONVECTION REGION W OF 70W. OTHERWISE...ANTI 
CYCLONIC FLOW ALOFT CONTINUES TO DOMINATE ELSEWHERE OUT OF THE 
CONVECTION REGION...LEAVING THE AREA RELATIVELY CLEAR WITH A  
FEW ISOLATED SHOWERS S IF HISPANIOLA AND N OF HONDURAS. EXPECT 
MORE CONVECTION DEVELOPING OVER THE SW CARIBBEAN BASIN OVER THE 
NEXT 24 HOURS.

ATLANTIC OCEAN...
A BROAD UPPER LEVEL TROUGH MOVES ACROSS THE NW ATLC SUPPORTING A 
COLD FRONT EXTENDING SW ALONG 32N58W 2762W TO 26N69W GENERATING 
SCATTERED SHOWERS AND THUNDERSTORMS WITHIN 50/100 NM E OF THE 
FRONT. IN THE MEAN TIME...AN UPPER LEVEL RIDGE OF HIGH PRESSURE 
BUILDS BEHIND THE FRONT ACROSS THE W ATLC BASIN ANCHORED BY A 
1018 MB HIGH NEAR 35N70W. THE REMAINDER OF THE ATLC E OF THE 
FRONT IS DOMINATED BY A BROAD SURFACE RIDGE ANCHORED BY A STRONG 
1029 MB HIGH CENTERED NEAR 35N30W.

F0R ADDITIONAL INFORMATION PLEASE VISIT
HTTP://WWW.HURRICANES.GOV/MARINE

$$

GARCIA