000 AXNT20 KNHC 220550 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0500 UTC. ...TROPICAL WAVES... TROPICAL WAVE EXTENDS FROM 7N37W THROUGH A WEAK 1011 MB LOW NEAR 4N29W TO 1N40W 5-10 KT. WAVE WAS RELOCATED EARLIER TODAY TO COINCIDE WITH THE SURFACE CIRCULATION. WAVE IS EMBEDDED WITHIN A LOW AMPLITUDE MOISTURE MAXIMUM ON THE TOTAL PRECIPITABLE WATER IMAGERY. THIS WAVE CONTINUES TO DISRUPTS THE ITCZ. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 3N-6N BETWEEN 38W- 41W. CLUSTERS OF ISOLATED MODERATE CONVECTION DOT THE AREA FROM 4N-7N BETWEEN 33W-38W. TROPICAL WAVE EXTENDS FROM 18N69W TO INLAND OVER SOUTH AMERICA TO NEAR 10N70W MOVING W-NW AT 15-20 KT OVER THE PAST 24 HOURS. WAVE IS EMBEDDED WITHIN A WEAK MOISTURE MAXIMUM ON THE TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS DOT THE CARIBBEAN FROM 15N-18N BETWEEN 64W-71W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL ATLC NEAR 11N15W CONTINUING TO 8N19W WHERE THE ITCZ BEGINS AND CONTINUES ALONG 5N28W TO 5N36W. SCATTERED MODERATE/ISOLATED CONVECTION IS OFF THE COAST OF AFRICA FROM 7N-9N BETWEEN 14W- 17W. CLUSTERS OF SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE WITHIN 30 NM OF THE MONSOON TROUGH/ITCZ E OF 24W TO THE COAST OF AFRICA. ...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 OVER THE FLORIDA PENINSULA WITH S TO SE RETURN FLOW COVERING THE GULF. WATER VAPOR IMAGERY INDICATES STRONG SUBSIDENCE AND DRY STABLE AIR ALOFT DOMINATING THE E GULF. THE UPPER RIDGE IS DRAWING MOISTURE ACROSS MEXICO TO OVER THE W GULF. LOW LEVEL CLOUDS ARE OVER THE W GULF N OF 22N W OF 93W LEAVING THE REMAINDER OF THE GULF UNDER CLEAR SKIES TONIGHT. ISOLATED SHOWERS ARE POSSIBLE WITHIN 30 NM OF 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 S OF 12N SW FLOW ALOFT. THE UPPER RIDGE OVER THE GULF OF MEXICO DIPS OVER THE NW CARIBBEAN GIVING THE AREA N OF 16N W OF 80W 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 10N83W ARE GENERATING SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS S OF 12N BETWEEN 74W- 80W AND S OF 10N W OF 80W. 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 IN GULF OF HONDURAS WITH STRONGER NE WINDS JUST W OF WAVE AXIS AND OFF COAST OF COLOMBIA THROUGH SUN. HISPANIOLA... AFTERNOON THUNDERSTORMS HAVE COMPLETELY DIED OUT. AN UPPER RIDGE BEGINS JUST TO THE NE TO THE ISLAND EXTENDING NW OVER THE W ATLC. WATER VAPOR IMAGERY SHOWERS DEEP LAYER MOISTURE OVER THE ISLAND SO SOME ISOLATED SHOWERS ARE POSSIBLE OVER THE INTERIOR SECTIONS OF THE ISLAND. THE UPPER RIDGE IS JUST TO THE E OF AN UPPER TROUGH THAT IS MOVING E. THE TROPICAL WAVE TO THE S CONTINUES TO TRACK W. THIS COULD BRING HEAVY RAIN MAINLY TO HAITI OVER THE NEXT DAY OR SO. ATLANTIC OCEAN... A SHORTWAVE UPPER TROUGH EXTENDS FROM AN UPPER LOW NEAR 32N78W OVER THE BAHAMA ISLANDS TO OFF THE COAST OF CUBA NEAR 21N75W AND IS AMPLIFYING AN UPPER RIDGE THAT EXTENDS FROM N OF PUERTO RICO NEAR 20N66W NW TO BEYOND 32N75W. THIS IS ENHANCING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS OVER THE BAHAMAS FROM 22N-27N BETWEEN 75W-79W. A SURFACE RIDGE EXTENDS FROM A 1025 MB HIGH NEAR 32N58W TO OVER FLORIDA AND ALONG THE EASTERN SEABOARD. A BROAD UPPER TROUGH COVERS THE CENTRAL ATLC SUPPORTING A COLD FRONT THAT ENTERS THE REGION NEAR 32N43W TO 28N49W WHERE IT DISSIPATES TO 27N56W. SCATTERED SHOWERS ARE WITHIN 120 NM E OF THE FRONT N OF 30N. A WEAK SURFACE TROUGH IS TO THE S EXTENDING FROM 29N47W TO 25N49W. A BROAD SURFACE RIDGE COVERS THE E ATLC ANCHORED BY A 1036 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