943 
AXNT20 KNHC 221045
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT WED MAY 22 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 
1000 UTC.

...TROPICAL WAVES...                                     
TROPICAL WAVE EXTENDS FROM 7N38W THROUGH A WEAK 1011 MB LOW NEAR 
4N39.5W TO 2N40W MOVING W NEAR 10 KT. WAVE IS EMBEDDED WITHIN A 
LOW AMPLITUDE MOISTURE MAXIMUM ON THE TOTAL PRECIPITABLE WATER 
IMAGERY. THIS WAVE CONTINUES TO DISRUPTS THE ITCZ. CLUSTERS OF  
SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE WITHIN 75/90 
NM OF LINE FROM 7N36W TO 4N43W.  

TROPICAL WAVE EXTENDS ALONG 70W/71W S OF 18N TO INLAND OVER 
SOUTH AMERICA MOVING W-NW AT 15-20 KT. WAVE IS EMBEDDED WITHIN A 
WEAK MOISTURE MAXIMUM ON THE TOTAL PRECIPITABLE WATER IMAGERY. 
SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE FROM 17N-18N 
BETWEEN 66W-71W. 

...ITCZ/MONSOON TROUGH...                                     
THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL 
ATLC NEAR 10N14W CONTINUING TO 6N21W WHERE THE ITCZ BEGINS AND 
CONTINUES ALONG 5N29W TO 5N38W. CLUSTERS OF SCATTERED SHOWERS 
AND ISOLATED THUNDERSTORMS ARE N OF 3N TO THE SW COAST OF AFRICA 
E OF 7W TO ACROSS THE PRIME MERIDIAN...FROM 10N-12N E OF 17W TO 
THE W COAST OF AFRICA...AND FROM 2N-9N BETWEEN 16W-21W. 

...DISCUSSION...

GULF OF MEXICO...                                                
A BROAD UPPER RIDGE AXIS EXTENDS FROM THE E PACIFIC REGION 
ACROSS S MEXICO/W YUCATAN PENINSULA TO THE N GULF COAST NEAR 
MOBILE ALABAMA COVERING THE ENTIRE GULF. A SURFACE RIDGE EXTENDS 
FROM THE W ATLC TO THE FLORIDA PENINSULA WITH S TO SE RETURN 
FLOW COVERING THE GULF. THE UPPER RIDGE IS DRAWING MOISTURE 
ACROSS MEXICO TO OVER THE W GULF. LOW LEVEL CLOUDS ARE OVER THE 
FAR W GULF LEAVING MOST OF THE GULF UNDER CLEAR SKIES THIS 
MORNING. RADAR INDICATES ISOLATED SHOWERS ARE FROM S OF 26N E OF 
83W ACROSS S FLORIDA AND THE FLORIDA KEYS. COLD FRONT WILL MOVE 
INTO NE GULF LATE FRI THEN DRIFT SE THROUGH SUN. 

CARIBBEAN SEA...                                               
AN UPPER RIDGE AXIS EXTENDS ALONG THE N PORTION OF SOUTH AMERICA 
GIVING THE SW CARIBBEAN SW FLOW ALOFT. THE UPPER RIDGE OVER THE 
GULF OF MEXICO DIPS OVER THE NW CARIBBEAN GIVING THE AREA NW 
FLOW ALOFT WHILE THE REMAINDER OF THE AREA IS UNDER NEAR ZONAL 
WESTERLY FLOW ALOFT. THE MONSOON TROUGH EXTENDS FROM COLOMBIA 
NEAR 10N75W THROUGH A 1009 MB LOW NEAR 11N80W TO ACROSS COSTA 
RICA NEAR 11N83W ARE GENERATING SCATTERED SHOWERS AND POSSIBLE 
ISOLATED THUNDERSTORMS S OF 12N BETWEEN W OF 80W AND WITHIN 60 
NM ALONG THE COAST OF COLOMBIA. CLUSTERS OF SCATTERED SHOWERS/ 
ISOLATED THUNDERSTORMS CONTINUE OVER THE N/CENTRAL CARIBBEAN N 
OF 18N BETWEEN 75W-80W. THE E CARIBBEAN IS COVERED IN THE 
TROPICAL WAVE SECTION ABOVE. W ATLC SURFACE RIDGE WILL MAINTAIN 
MODERATE TO FRESH SE TRADE WINDS WITH THE STRONGEST WINDS IN THE 
GULF OF HONDURAS THROUGH SUN. 

HISPANIOLA...                                                  
AN UPPER RIDGE BEGINS JUST N OF THE ISLAND EXTENDING NW OVER THE 
W ATLC. TOTAL PRECIPITABLE WATER IMAGERY INDICATES MOISTURE IN 
PLACE ACROSS THE ISLAND SO SOME ISOLATED SHOWERS ARE POSSIBLE 
OVER THE INTERIOR SECTIONS OF THE ISLAND. THE UPPER RIDGE N OF 
THE ISLAND IS MOVING E AS THE TROPICAL WAVE CONTINUES TO TRACK 
W. THIS COULD BRING RAIN AND POSSIBLE THUNDERSTORMS TO 
HISPANIOLA OVER THE NEXT DAY OR SO. 

ATLANTIC OCEAN...                                               
A SHORTWAVE UPPER TROUGH REMAINS OVER THE FAR W ATLC AMPLIFYING 
AN UPPER RIDGE JUST TO THE E EXTENDS FROM N OF HISPANIOLA TO OFF 
THE GEORGIA COAST ENHANCING SCATTERED SHOWERS/ISOLATED 
THUNDERSTORMS OVER THE BAHAMAS FROM 21N-31N BETWEEN 74W-79W WITH 
ISOLATED SHOWERS FROM 22N TO 30N W OF 79W TO THE COAST OF 
FLORIDA AND OVER S FLORIDA. A SURFACE RIDGE EXTENDS FROM A 1024 
MB HIGH NEAR 32N59W TO FLORIDA AND THE EASTERN SEABOARD. A BROAD 
UPPER TROUGH COVERS THE CENTRAL ATLC SUPPORTING A DYING 
STATIONARY FRONT THAT ENTERS THE REGION NEAR 32N43W TO 27N52W. 
SCATTERED SHOWERS ARE WITHIN 120 NM OF LINE FROM 29N41W TO 
BEYOND 32N39W. A WEAK SURFACE TROUGH IS TO THE S EXTENDING FROM 
27N47W TO 24N50W. A BROAD SURFACE RIDGE COVERS THE E ATLC 
ANCHORED BY A 1035 MB HIGH WELL N OF THE AZORES. A WEAK TROUGH 
DEVELOPS OFF NE FLORIDA N OF GRAND BAHAMA THU. COLD FRONT WILL 
MOVE INTO NW PORTION FRI AND DRIFT IN E ACROSS WATERS N OF 27N 
THROUGH SUN.

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

$$
PAW