000
AXNT20 KNHC 311741
TWDAT 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL 
205 PM EDT THU OCT 31 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1715 UTC.

...TROPICAL WAVES...                                             
TROPICAL WAVE IN THE CARIBBEAN EXTENDS FROM 20N85W TO INLAND 
OVER CENTRAL AMERICA NEAR 15N85W MOVING W 15-20 KT. WAVE IS 
BENEATH AN UPPER RIDGE WHICH IS ENHANCING SCATTERED SHOWERS/ 
ISOLATED THUNDERSTORMS S OF 18N W OF 85W. 

...THE ITCZ/THE MONSOON TROUGH...                                
THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL 
ATLC NEAR 6N10W AND CONTINUES TO 4N17W WHERE THE ITCZ BEGINS AND 
CONTINUES ALONG 4N22W 7N37W 5N49W TO SOUTH AMERICA NEAR 5N53W. 
CLUSTER OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE  
FROM 3N-7N BETWEEN 10W-20W AND FROM 8N-12N BETWEEN 17W-21W. 
 
...DISCUSSION...

GULF OF MEXICO...                                            
BROAD UPPER RIDGE DOMINATES THE AREA ANCHORED IN THE SW GULF 
NEAR 21N95W AND EXTENDS OVER THE W ATLC AND W CARIBBEAN. 
SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE MOVING OFF TEXAS 
AND LOUISIANA AHEAD OF A FRONT THAT IS WELL INLAND WITHIN 45 NM 
ALONG THE COAST FROM VERMILION BAY LOUISIANA TO BROWNSVILLE 
TEXAS. ISOLATED SHOWERS DOT THE AREA N OF 23N W OF 93W. THE 
SURFACE RIDGE ANCHORED BY A 1022 MB HIGH OVER SOUTH 
CAROLINA/GEORGIA EXTENDS OVER BETWEEN CEDAR KEY AND TAMPA TO 
24N90W. THIS IS LEAVING THE REMAINDER OF THE GULF UNDER MOSTLY 
CLEAR SKIES THIS AFTERNOON. COLD FRONT WILL MOVE OFF THE TEXAS 
COAST LATER TODAY REACHING FROM SE LOUISIANA TO SE TEXAS EARLY 
FRI FROM NORTH FLORIDA TO W BAY OF CAMPECHE EARLY SAT THEN SE OF 
THE AREA BY EARLY SUN. HIGH PRESSURE WILL REBUILD OVER THE GULF 
IN THE WAKE OF THE FRONT.

CARIBBEAN SEA...                                               
THE BROAD UPPER RIDGE OVER THE GULF OF MEXICO COVERS THE W 
CARIBBEAN W OF A LINE FROM CUBA NEAR 21N77W TO PANAMA/COSTA RICA 
BORDER. THE UPPER TROUGH OVER THE W ATLC IS BECOMING CUT OFF 
OVER THE CARIBBEAN AND THE TROUGH AXIS EXTENDS FROM HISPANIOLA 
THROUGH AN UPPER LOW NEAR 14N72W TO COLOMBIA/PANAMA BORDER. A 
SHEAR LINE EXTENDS FROM THE W/CENTRAL ATLC TO THE E TIP OF THE 
DOMINICAN REPUBLIC. SOUTHERLY FLOW ALOFT E OF THE UPPER TROUGH 
COUPLED WITH A SURFACE TROUGH THAT EXTENDS FROM THE LEEWARD 
ISLANDS NEAR 17N62W TO THE COAST OF VENEZUELA NEAR 11N64W ARE 
ENHANCING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS SPREADING 
ACROSS THE AREA FROM 10N-17N E OF 73W TO OVER THE LESSER 
ANTILLES. THE REMAINDER OF THE CARIBBEAN IS UNDER MOSTLY CLEAR 
SKIES THIS AFTERNOON. TROPICAL WAVE WILL MOVE W OF THE AREA FRI. 
SURFACE TROUGH IN THE E CARIBBEAN WILL MOVE INTO THE CENTRAL 
CARIBBEAN TONIGHT WHERE IT WILL STALL AND LINGER THROUGH MON. A 
WEAK LOW MAY FORM ALONG THE TROUGH.

HISPANIOLA...                                                  
CURRENTLY SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE OVER NE 
DOMINICAN REPUBLIC DUE TO THE SHEAR LINE. SURFACE TROUGH IN THE 
E CARIBBEAN WILL MOVE INTO THE CENTRAL CARIBBEAN TONIGHT WHERE 
IT WILL STALL AND LINGER THROUGH MON. THIS WILL INCREASE 
SHOWERS/THUNDERSTORMS AS THE SURFACE TROUGH MOVES ACROSS THE 
ISLAND THIS WEEKEND. 

ATLANTIC OCEAN...                                                
THE UPPER RIDGE OVER OVER THE GULF OF MEXICO EXTENDS OVER THE W 
ATLC TO 72W. AN UPPER TROUGH COVERS THE REMAINDER OF THE W ATLC 
INTO THE CENTRAL ATLC THEN ACROSS HISPANIOLA INTO THE CARIBBEAN 
SUPPORTING A COLD FRONT THAT ENTERS THE AREA NEAR 32N50W TO 
27N57W WHERE IT BECOMES A SHEAR LINE ALONG 19N65W TO THE E TIP 
OF HISPANIOLA. SCATTERED SHOWERS AND POSSIBLE ISOLATED 
THUNDERSTORMS ARE WITHIN 150 NM EITHER SIDE OF THE SHEAR LINE E 
OF 66W. A SURFACE RIDGE IS BUILDING S OVER THE W ATLC IN WAKE OF 
THE RECENT FRONT ANCHORED BY A 1027 MB HIGH N OF BERMUDA. A 
SURFACE TROUGH IS E OF THE LESSER ANTILLES EXTENDING FROM 15N53W 
TO 8N53W WITH SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS 
WITHIN 45 NM EITHER SIDE OF THE TROUGH. THE REMAINDER OF THE 
ATLC BASIN IS DOMINATED BY A SURFACE RIDGE ANCHORED BY A PAIR OF 
1027 MB HIGHS NEAR THE AZORES. THE SHEAR LINE WILL DISSIPATE 
THROUGH SAT. A COLD FRONT WILL MOVE OFF SE CONUS LATE FRI NIGHT 
INTO EARLY SAT. THE COLD FRONT WILL REACH FROM NEAR 31N75W TO SE 
FLORIDA BY SAT EVENING FROM NEAR BERMUDA TO E CUBA BY LATE SUN 
BEFORE MOVING INTO THE CENTRAL ATLC MON.

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

$$
PAW