000
AXNT20 KNHC 140549
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT TUE MAY 14 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 
0445 UTC.

...ITCZ/MONSOON TROUGH...                                     

THE MONSOON TROUGH EXTENDS FROM THE COAST OF GUINEA NEAR 11N15W 
TO 6N19W. THE ITCZ BEGINS FROM 6N19W AND CONTINUES ALONG 4N30W 
3N40W 3N47W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS 
FROM 3N-5N BETWEEN 28W-44W.

...DISCUSSION...

GULF OF MEXICO...                                               
A COLD FRONT CONTINUES TO MOVE SLOWLY THROUGH THE GULF OF MEXICO 
CURRENTLY EXTENDING ACROSS SOUTH FLORIDA FROM 26N80W TO 23N90W 
WHERE IT BECOMES STATIONARY ALONG 23N95W 19N95W...AS OF 0300 
UTC. A PRE-FRONTAL TROUGH IS IN THE SW GULF ALONG 22N94W 19N93W. 
ISOLATED SHOWERS AND POSSIBLE THUNDERSTORMS EXTEND WEST OF THE 
FRONT AND INTO EASTERN MEXICO SOUTH OF 95N. THE REMAINDER OF THE 
BASIN IS UNDER MOSTLY CLEAR SKIES. SURFACE RIDGING IS BUILDING 
ACROSS THE NORTHERN GULF AROUND TWO 1024 MB HIGHS NEAR 30N89W 
AND 30N93W. LIGHT ANTI-CYCLONIC FLOW IS AROUND THE TWO HIGH 
CENTERS INCREASING TO 15 KT JUST NORTH OF THE FRONTAL BOUNDARY. 
WINDS TO THE SOUTH OF THE FRONT ARE ALSO REACHING 15 KT. 
ALOFT...SOUTHWEST TO WEST FLOW COVERS THE BASIN AROUND A BROAD 
UPPER LEVEL RIDGE COVERING MUCH OF THE CARIBBEAN. THE EASTERN 
PORTION OF THE FRONT WILL CONTINUE TO MOVE EAST WHILE THE 
WESTERN PORTION WILL LIKELY DISSIPATE. MOISTURE OVER THE SW GULF 
WILL ALSO LIFT NORTH AS RETURN FLOW BUILDS AROUND THE WESTERN 
SIDE OF THE SURFACE RIDGE. 
 
CARIBBEAN SEA...                                                 
MOSTLY FAIR CONDITIONS SPREAD ACROSS THE CARIBBEAN DUE TO DRY 
AIR ALOFT AROUND AN UPPER LEVEL RIDGE ACROSS MUCH OF THE 
CARIBBEAN ALONG 78W...AND AN UPPER LEVEL TROUGH WITH AXIS JUST 
EAST OF THE LESSER ANTILLES. ONLY A SMALL AREA OF WIDELY 
ISOLATED SHOWERS ARE MOVING THROUGH THE FAR EASTERN PORTION OF 
THE BASIN. POSSIBLE ISOLATED SHOWERS ARE ALSO OVER HISPANIOLA. 
TRADEWIND FLOW OF 15-20 KT DOMINATES THE MAJORITY OF THE EASTERN 
AND CENTRAL CARIBBEAN WITH A FEW 25 KT WINDS NEAR THE COAST OF 
COLOMBIA. LITTLE CHANGE IS EXPECTED OVER THE NEXT 24 HOURS. 
THERE MAY BE AN INCREASE IN MOISTURE ACROSS THE NORTHERN 
CARIBBEAN ISLANDS AS THE FRONTAL BOUNDARY IN THE WEST ATLC AND 
GULF OF MEXICO MOVES EASTWARD JUST NORTH OF THE BASIN.  

ATLANTIC OCEAN...                                               
AN UPPER LEVEL TROUGH JUST NORTH OF THE DISCUSSION AREA ALONG 
74W SUPPORTS A COLD FRONT THAT ENTERS THE DISCUSSION AREA NEAR 
32N71W AND CONTINUES TO SOUTH FLORIDA ALONG 26N77W 26N80W...AS 
OF 0300 UTC. SCATTERED SHOWERS ARE UP TO 120 NM EAST OF THE AXIS 
NORTH OF 28N. A WEAK SURFACE TROUGH IS TO THE SOUTH ALONG 25N71W 
20N72W. NO SHOWER ACTIVITY IS ASSOCIATED WITH THE TROUGH EXCEPT 
FOR A FEW POSSIBLE ISOLATED SHOWERS ACROSS HISPANIOLA TO THE 
SOUTH. A RIDGE TROUGH RIDGE PATTERN COVERS THE REMAINDER OF THE 
UPPER LEVELS ACROSS THE BASIN. THE RIDGE RIDGE IS NARROW AND 
ALONG 58W. THE UPPER TROUGH IS ALSO NARROW AND EXTENDS FROM 
32N42W TO JUST EAST OF THE WINDWARD ISLANDS NEAR 11N60W. THE 
SECOND UPPER RIDGE IS BROAD AND COVERS THE MAJORITY OF THE 
TROPICAL ATLC CENTERED NEAR 8N33W. AT THE SURFACE...A BROAD 
UPPER LEVEL RIDGE DOMINATES THE CENTRAL AND EASTERN ATLC 
ANCHORED BY A 1040 MB HIGH NEAR 42N39W. FAIR CONDITIONS SPREAD 
ACROSS THIS AREA. 
 
FOR ADDITIONAL INFORMATION PLEASE VISIT 
HTTP://WWW.HURRICANES.GOV/MARINE

AT THE REQUEST OF METEO-FRANCE AND THE METEOROLOGICAL SERVICES OF 
HAITI AND THE DOMINICAN REPUBLIC...THE TROPICAL ANALYSIS AND 
FORECAST BRANCH (TAFB) WILL BEGIN PROVIDING...ON A TEMPORARY 
BASIS...A SEPARATE DETAILED SECTION WITHIN THE ATLANTIC TROPICAL 
WEATHER DISCUSSION (TWDAT). IT WILL COVER BOTH HAITI AND THE 
DOMINICAN REPUBLIC DUE TO THE SHARED GEOGRAPHY OF BOTH COUNTRIES 
ON THE ISLAND OF HISPANIOLA.

THE SECTION BEGINS ON MAY 15 2013 AT 1800 UTC...2 PM EDT. IT 
WILL PROVIDE GUIDANCE FOR SIGNIFICANT WEATHER EVENTS THAT ARE 
EXPECTED TO IMPACT THE REGION THROUGH 48 HOURS...WITH THE FOCUS 
ON ASSESSING THE POTENTIAL FOR HEAVY RAINFALL.

$$
WALTON