000
AXNT20 KNHC 261103
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT FRI JUL 26 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1015 UTC.

...SPECIAL FEATURE...                                            
TROPICAL STORM DORIAN IS CENTERED NEAR 17.1N 41.5W AT 26/0900 
UTC OR ABOUT 1240 NM E OF THE NORTHERN LEEWARD ISLANDS MOVING W-
NW AT 17 KT. MAXIMUM SUSTAINED WIND SPEED IS 45 KT WITH GUSTS TO 
55 KT. MINIMUM CENTRAL PRESSURE IS 1001 MB. PLEASE SEE THE 
FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT4/WTNT24 KNHC 
AND THE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT4/WTNT34 
KNHC FOR MORE DETAILS. DORIAN IS LESS ORGANIZED WITH CLUSTERS OF 
SCATTERED MODERATE/ISOLATED STRONG CONVECTION FROM 16N-19N 
BETWEEN 38W-43W. 

...TROPICAL WAVES...                                             
TROPICAL WAVE IS CURRENTLY INLAND OVER THE YUCATAN PENINSULA 
ALONG 90W FROM 21N TO ACROSS GUATEMALA INTO THE E PACIFIC REGION 
MOVING W 10-15 KT. NO ASSOCIATED SHOWERS/CONVECTION IN THE 
CARIBBEAN SEA OR GULF OF MEXICO.
 
...THE ITCZ/THE MONSOON TROUGH...                                
THE MONSOON TROUGH AXIS EXTENDS ACROSS AFRICA INTO THE E 
TROPICAL ATLC NEAR 12N16W AND CONTINUES TO 9N20W WHERE THE ITCZ 
BEGINS AND CONTINUES ALONG 7N26W TO 12N32W THEN RESUMES S OF 
TROPICAL STORM DORIAN NEAR 13N38W AND CONTINUES TO NEAR 8N46W. 
SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 90 NM 
ALONG THE COAST OF SIERRA LEONE AND FROM 7N-10N BETWEEN 19W-22W. 
 
...DISCUSSION...

GULF OF MEXICO...                                              
AN UPPER RIDGE EXTENDS ACROSS TEXAS INTO THE GULF ACROSS S 
FLORIDA CONTINUING INTO THE W ATLC GIVING THE GULF MOSTLY N TO 
NE FLOW ALOFT. A SURFACE TROUGH AT 26/0900 UTC EXTENDS FROM THE 
W ATLC ACROSS CENTRAL FLORIDA S OF TAMPA TO 27N86W WITH 
SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 45 NM S OF THE 
TROUGH E OF 85W. A WEAK SURFACE RIDGE DOMINATES THE REMAINDER OF 
THE GULF EXTENDING FROM THE W ATLC ACROSS S FLORIDA TO THE COAST 
OF TEXAS AND MEXICO WITH A 1018 MB HIGH NEAR 24N90W LEAVING THE 
REMAINDER OF THE GULF WITH CLEAR SKIES THIS MORNING. SURFACE 
RIDGE WILL PREVAIL ACROSS THE GULF THROUGH TUE.

CARIBBEAN SEA...                                                 
AN UPPER LOW COVERS THE NW CARIBBEAN W OF 84W CENTERED OVER 
BELIZE/GUATEMALA WHILE AN UPPER RIDGE COVERS THE REMAINDER OF 
THE CARIBBEAN S OF 17N AND ANCHORED OFF THE COAST OF E VENEZUELA 
JUST E OF TRINIDAD. THE UPPER TROUGH OVER THE W ATLC DIPS S OVER 
THE NE CARIBBEAN N OF 17N. THE MONSOON TROUGH EXTENDS ALONG 
9N/10N FROM COLOMBIA TO ACROSS COSTA RICA INTO THE E PACIFIC 
REGION GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 
10N AND WITHIN 60 NM ALONG THE COAST OF COSTA RICA AND NICARAGUA 
S OF 13N. THIS IS LEAVING THE REMAINDER OF THE CARIBBEAN UNDER 
MOSTLY CLEAR SKIES THIS MORNING. TROPICAL STORM DORIAN IN THE 
CENTRAL ATLC WILL MOVE QUICKLY W-NW REACHING NE OF THE LEEWARD 
ISLANDS SAT NIGHT THEN CONTINUE N OF THE VIRGIN ISLANDS AND 
PUERTO RICO TOWARD SOUTHERN BAHAMAS/TURKS AND CAICOS THROUGH TUE.

HISPANIOLA...                                                  
CURRENTLY SKIES ARE CLEAR ACROSS ALL OF HISPANIOLA. AN UPPER 
TROUGH EXTENDS FROM THE W ATLC OVER HISPANIOLA. AFTERNOON 
SHOWERS AND THUNDERSTORMS ARE POSSIBLE WITH DAYTIME HEATING AND 
WILL BE ENHANCED BY THE UPPER TROUGH THAT WILL PERSIST THROUGH 
TUE. TROPICAL STORM WILL APPROACHING HISPANIOLA TUE.

ATLANTIC OCEAN...                                               
AN UPPER TROUGH DIPS S OVER THE FAR W ATLC N OF 28N W OF 74W TO 
OVER NE FLORIDA SUPPORTING A SURFACE TROUGH THAT EXTENDS THROUGH 
32N75W ACROSS CENTRAL FLORIDA NEAR MELBOURNE. THE UPPER RIDGE 
OVER THE GULF OF MEXICO EXTENDS OVER THE REMAINDER OF THE W ATLC 
TO 73W PROVIDING DIFFLUNCE ALOFT TO GENERATE SCATTERED SHOWERS/ 
ISOLATED THUNDERSTORMS WITHIN 150 NM E OF THE SURFACE TROUGH. 
SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE N OF 
26N BETWEEN 70W-75W. AN UPPER LOW IS TO THE E CENTERED NEAR 
25N63W COVERING THE AREA N OF 17N FROM 50W-74W INCLUDING PUERTO 
RICO AND HISPANIOLA WHICH IS GENERATING SCATTERED SHOWERS/ 
THUNDERSTORMS WITHIN 150 NM OF LINE FROM 23N64W TO 34N59W AND 
FROM 25N-29N BETWEEN 50W-53W. A SURFACE RIDGE DOMINATES THE 
REMAINDER OF THE ATLC ANCHORED BY A 1034 MB HIGH W OF THE 
AZORES. SURFACE RIDGE WILL PREVAIL THROUGH THIS WEEKEND. 
TROPICAL STORM DORIAN IN THE CENTRAL ATLC WILL MOVE QUICKLY W-NW 
REACHING NE OF THE LEEWARD ISLANDS SAT NIGHT THEN CONTINUE N OF 
THE VIRGIN ISLANDS AND PUERTO RICO TOWARD SOUTHERN BAHAMAS/TURKS 
AND CAICOS THROUGH TUE.

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

$$
PAW