Atlantic Tropical Weather Discussion

000
AXNT20 KNHC 192355
TWDAT 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
805 PM EDT WED JUN 19 2013

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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2245 UTC.

...SPECIAL FEATURES...                                   
TROPICAL STORM BARRY IS CENTERED NEAR 19.6N 95.5W AT 20/0000 UTC 
OR ABOUT 50 NM ENE OF VERACRUZ MEXICO MOVING W AT 5 KT. 
ESTIMATED MINIMUM CENTRAL PRESSURE IS 1005 MB. MAXIMUM SUSTAINED 
WIND SPEED IS 40 KT WITH GUSTS TO 50 KT. SCATTERED 
MODERATE/STRONG CONVECTION IS FROM 16N-21N BETWEEN 89W-93W. 
SIMILAR ACTIVITY IS FROM 19N-23N BETWEEN 93W-98W.  SEE LATEST 
NHC INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS 
MIATCPAT2/WTNT32 AND THE FULL NHC FORECAST/ADVISORY UNDER 
AWIPS/WMO HEADERS MIATCMAT2/WTNT22 KNHC FOR MORE DETAILS.

...TROPICAL WAVES...                                      
TROPICAL WAVE IS ALONG 15N31W TO 6N32W MOVING WEST NEAR 15 KT. 
THE WAVE LIES ON THE WESTERN SIDE OF A SURGE IN DEEP LAYER 
MOISTURE EVIDENT IN TOTAL PRECIPITABLE WATER IMAGERY. THERE IS 
ALSO A CLEARING IN THE LARGE AREA OF SAHARAN DUST THAT SPREADS 
ACROSS THE TROPICAL ATLC. DUE TO THE PRESENCE OF THE 
DUST...NO DEEP CONVECTION IS ASSOCIATED WITH THE WAVE.

TROPICAL WAVE EXTENDS FROM 21N65W TO 13N66W MOVING W AT 10-15 
KT. THE WAVE COINCIDES WITH A SURGE OF DEEP LAYER MOISTURE 
PRESENT IN TOTAL PRECIPITABLE WATER IMAGERY. AN UPPER LEVEL 
TROUGH IS ALSO PROVIDING DIFFLUENT FLOW ALOFT OVER THE WAVE. 
SCATTERED MODERATE CONVECTION IS FROM 14N-24N BETWEEN 62W-67W. 

...ITCZ/MONSOON TROUGH...                                     
THE MONSOON TROUGH EXTENDS FROM THE COAST OF GUINEA-BISSAU NEAR 
12N16W TO 8N22W. THE ITCZ BEGINS NEAR 8N22W AND CONTINUES ALONG 
7N36W 5N56W. SCATTERED MODERATE/STRONG CONVECTION IS FROM 6N-8N 
BETWEEN 11W-16...AND FROM 10N-12N BETWEEN 16W-19W. SCATTERED 
MODERATE/ISOLATED STRONG CONVECTION IS FROM 3N-7N BETWEEN 50W-
59W.

...DISCUSSION...

GULF OF MEXICO...                                         
SURFACE RIDGING DOMINATES THE NORTHERN HALF OF THE GULF OF 
MEXICO CENTERED AROUND A 1020 MB HIGH NEAR 26N88W. TROPICAL 
STORM BARRY IS IMPACTING THE SOUTHWEST GULF AND SUPPORTING 
SCATTERED SHOWERS/ISOLATED THUNDERSTORMS FROM 18N-23N BETWEEN 
90W-98W. MORE SHOWERS/THUNDERSTORMS CONTINUE INTO SOUTHERN 
MEXICO...YUCATAN PENINSULA...AND GUATEMALA. SEE SPECIAL FEATURES 
FOR MORE DETAILS. NORTH OF THE CIRCULATION OF BARRY...WINDS ARE 
LIGHT AND ANTI-CYCLONIC. SKIES ARE MOSTLY CLEAR DUE TO DRY AIR 
ALOFT AROUND AN UPPER LEVEL RIDGE TO THE SOUTH THAT EXTENDS OVER 
THE YUCATAN PENINSULA. CLUSTERS OF SHOWERS/THUNDERSTORMS ARE 
ALSO OVER THE SOUTHERN HALF OF THE FLORIDA PENINSULA. BARRY WILL 
CONTINUE TO IMPACT THE SW GULF...WHILE SURFACE RIDGING REMAINS 
OVER THE NORTHERN GULF. 

CARIBBEAN SEA...                                              
MOSTLY CLEAR SKIES ARE ACROSS THE WESTERN AND CENTRAL CARIBBEAN 
DUE TO DRY AIR ALOFT AROUND AN UPPER LEVEL RIDGE OVER THE 
YUCATAN PENINSULA...AND AROUND AN UPPER LEVEL TROUGH ALONG 71W. 
A FEW SHOWERS/THUNDERSTORMS ARE OVER THE FAR SW CARIBBEAN NEAR 
THE MONSOON TROUGH WHICH EXTENDS FROM COSTA RICA ALONG 9N TO 
NORTHERN COLOMBIA. THE UPPER TROUGH ALONG 71W IS PROVIDING MOIST 
AND DIFFLUENT FLOW ALOFT OVER THE EASTERN CARIBBEAN...WHICH IS 
ENHANCING ACTIVITY NEAR A TROPICAL WAVE. SCATTERED 
SHOWERS/ISOLATED THUNDERSTORMS ARE NORTH OF 14N EAST OF 67W. 
SCATTERED SHOWERS/THUNDERSTORMS ARE ALSO OVER CENTRAL 
HISPANIOLA. TRADEWIND FLOW OF 20-25 KT IS THROUGHOUT MUCH OF THE 
BASIN. EXPECT MOIST CONDITIONS OVER THE NORTHERN CARIBBEAN 
ISLANDS AS THE TROPICAL WAVE TRACKS WESTWARD. LITTLE CHANGE IS 
EXPECTED ELSEWHERE.

HISPANIOLA...                                            
MOISTURE NEAR A TROPICAL WAVE STILL TO THE EAST IS HELPING 
PRODUCE SCATTERED SHOWERS/THUNDERSTORMS OVER THE CENTRAL 
PORTIONS OF HISPANIOLA FROM 18N-20N BETWEEN 69W-73W. THE WAVE 
WILL CONTINUE TO BRING HIGHER MOISTURE LEVELS OVER THE ISLAND 
FOR AT LEAST THE NEXT 24 HOURS. 

ATLANTIC OCEAN...                                                
A BROAD RIDGE COVERS MUCH OF THE ATLC BASIN EXTENDING FROM A 
1033 MB AZORES HIGH. DRY AIR ALOFT AROUND THE WEST SIDE OF AN 
ELONGATED UPPER LOW NEAR 24N69W IS PROVIDING FAIR CONDITIONS 
OVER THE FAR WEST ATLC. THE UPPER LOW IS ADVECTING MOISTURE 
AROUND THE EAST SIDE ENHANCING CONVECTION NEAR A TROPICAL WAVE 
IN THE CARIBBEAN. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE 
FROM 19N-24N BETWEEN 62W-68W. FARTHER EAST...AN UPPER LEVEL 
RIDGE IS ALONG 55W...WHILE ANOTHER UPPER LOW IS CENTERED NEAR 
28N43W. THE UPPER LOW SUPPORTS A BROAD SURFACE TROUGH ALONG 
30N44W TO 23N46W. NO SHOWERS ARE ASSOCIATED WITH THE TROUGH. 
BROAD UPPER RIDGING DOMINATES THE TROPICAL ATLC...WHILE A THIRD 
WEAK UPPER LOW IS OVER THE EASTERN ATLC NEAR 26N25W. A SAHARAN 
AIR LAYER CONTINUES TO BE PRESENT OVER MUCH OF THE TROPICAL 
ATLC...EXCEPT NEAR THE TROPICAL WAVE...EXTENDING TO NEAR 57W.

FOR ADDITIONAL INFORMATION PLEASE VISIT 
WWW.HURRICANES.GOV/MARINE

$$
WALTON