000 AXNT20 KNHC 251759 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT MON MAR 25 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. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH PASSES THROUGH COASTAL SIERRA LEONE NEAR 7N12W TO 5N15W 3N19W. THE ITCZ CONTINUES FROM 3N19W TO EQ30W 2S41W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS N OF THE ITCZ AXIS FROM 1N-4N BETWEEN 25W AND 32W. ...DISCUSSION... THE GULF OF MEXICO... A SURFACE RIDGE HAS BEEN BUILDING OVER THE GULF ANCHORED BY A 1026 MB HIGH PRESSURE LOCATED OVER NORTHERN TEXAS NEAR 33N99W. THIS HIGH IS PROVIDING NORTHERLY-NORTHEASTERLY WINDS OF 20-25 KT TO THE ENTIRE BASIN. NORTHEASTERLY WINDS W OF 90W ARE BANKING LOW LEVEL CLOUDS ALONG THE E COAST OF MEXICO FROM MATAMOROS TO CIUDAD DEL CARMEN WHERE HAZE AND LIGHT FOG HAVE BEEN REPORTED. NO CONVECTIVE PRECIPITATION IS OBESERVED AT THE TIME. HOWEVER ISOLATED SHOWERS ARE POSSIBLE WITHIN 120 NM OF THE COASTLINE. IN THE MIDDLE TO UPPER LEVELS WESTERLY WIND FLOWS OVER THE REGION. WATER VAPOR IMAGERY SHOW DRY AIR ALOF FROM 82W TO 90W N OF 24N WHICH IS SUPPORTING FAIR WEATHER CONDITIONS OVER THE NE GULF. THE COLD FRONT THAT HAS BEEN MOVING ACROSS FLORIDA WITHIN THE LAST 24 HOURS NOW ENTERS THE SE GULF BY THE FLORIDA STRAITS NEAR 24N80W AND EXTENDS TO 23N82W WHERE IT TRANSITIONS TO A STATIONARY FRONT ALONG 22N84W 21N86W AND THEN ALONG THE EASTERN YUCATAN PENINSULA. RADAR IMAGERY INDICATE THAT THUNDERSTORMS ARE OCCURING WITHIN 50 NM EAST OF THE FRONTAL BOUNDARY OVER THE FLORIDA STRAITS. BOTH OBSERVATIONS OVER N YUCATAN PENINSULA AND THE SATELLITE COMPOSITE TOTAL PRECIPITABLE WATER INDICATE THAT RAINSHOWERS ARE ALSO OCCURING OVER THE YUCATAN CHANNEL. EXPECT LITTLE CHANGES OVER THE NEXT 24 HOURS. THE CARIBBEAN SEA... AS OF 1500 UTC A PREFRONTAL SURFACE TROUGH EXTENDS APPROXIMATELY 40 NM TO THE E OF THE YUCATAN PENINSULA EASTERN COAST ALONG 21N86W 19N86W 16N87W. OBSERVATIONS ALONG THE YUCATAN PENINSULA E COAST INDICATE BROKEN TO OVERCAST SKIES. RAINSHOWERS ACTIVITY IS POSSIBLE WITHIN 50 NM EITHER SIDE OF THE TROUGH AS SUGGESTED BY THE SATELLITE COMPOSITE TOTAL PRECIPITABLE WATER. WINDS OVER THE WESTERN CARIBBEAN W OF 78W N OF 14N ARE SOUTHEASTERLY IN THE RANGE OF 10-15 KT. EASTERLY TRADEWINDS IN THE RANGE OF 15-20 KT SPREAD OVER THE REMAINDER OF THE CARIBBEAN. WESTERLY- SOUTHWESTERLY WINDS FLOW OVER THE BASIN IN THE MIDDLE TO UPPER LEVELS AND VERY DRY AIR ALOFT IS SUPPORTING FAIR WEATHER CONDITIONS ACROSS MOST OF THE REGION. ISOLATED SHOWERS ARE POSSIBLE ALONG THE COAST OF COLOMBIA ASSOCIATED TO A 1008 MB LOW LOCATED NEAR THE NORTHERN COLOMBIA COASTLINE. OVER THE COURSE OF 24 HOURS...THE STATIONARY PORTION OF THE FRONTAL BOUNDARY OVER THE FLORIDA STRAITS AND THE YUCATAN PENINSULA WILL TRANSITION BACK TO A COLD FRONT AND WILL BE EXTENDING APPROXIMATELY FROM EASTERN CUBA TO HONDURAS. RAINSHOWES WILL CONTINUE OVER THE NW CARIBBEAN AND NORTHEASTERLY WINDS UP TO 25 KT WILL BUILD IN THE YUCATAN CHANNEL DOWN TO 17N AND W OF 81W. EXPECT LITTLE CHANGES ELSEWHERE. THE ATLANTIC OCEAN... AS OF 1500 UTC...A COLD FRONT EXTENDS OVER THE W ATLC FROM 30N73W TO 27N76W AND 23N82W WHERE IT TRANSITIONS TO A STATIONARY FRONT. RADAR IMAGERY INDICATE THAT THERE IS A LINE OF THUNDERSTORMS WITHIN 30 NM EAST OF THE FRONT S OF 26N. RAINSHOWERS ACTIVITY IS ALSO POSSIBLE FROM 26N-30N BETWEEN 70W AND 77W AS SUGGESTED BY THE SATELLITE COMPOSITE TOTAL PRECIPITABLE WATER IMAGERY. OVER THE CENTRAL AND EASTERN ATLC SURFACE RIDGING DOMINATE N OF 14N ANCHORED BY A 1019 MB HIGH NEAR 24N45W WEST OF A COLD FRONT AND A 1021 MB HIGH NEAR 29N18W EAST OF A COLD FRONT. THE COLD FRONT BETWEEN THE TWO HIGH PRESSURES EXTENDS FROM 30N31W TO 26N37W 22N45W AND IS BEING SUPPORTED BY A MIDDLE TO UPPER LEVEL NARROW TROUGH. ISOLATED SHOWERS ARE POSSIBLE ALONG THE COLD FRONT AS WELL AS 60 NM EAST OF IT. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ NR