000 AXNT20 KNHC 310004 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT FRI MAR 30 2012 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2345 UTC. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS W AFRICA TO THE COAST OF SIERRA LEONE AT 9N13W...AND CONTINUES SW TO 2N21W. THE ITCZ THEN CONTINUES FROM 2N21W TO 1N30W AND CROSSES THE EQUATOR AT 36W TO THE COAST OF BRAZIL AT 2S44W. SCATTERED STRONG CONVECTION IS WITHIN 30 NM S OF THE MONSOON TROUGH BETWEEN 15W-19W. SCATTERED MODERATE CONVECTION IS WITHIN 30 NM S OF THE ITCZ BETWEEN 24W-26W. ...DISCUSSION... GULF OF MEXICO... ALOFT...A RATHER WEAK UPPER RIDGE HAS SHIFTED EWD TO THE ERN PART OF THE GULF AS A SERIES OF SHORTWAVE TROUGHS ROTATING NEWD THROUGH THE ERN SECTOR OF THE CENTRAL U.S. LONGWAVE TROUGH. BOTH NWS RADAR DISPLAYS AND SATELLITE IMAGERY FROM DURING THE AFTERNOON AND EARLY EVENING HOURS AGAIN FOR THE SECOND DAY IN A SHOWING AN IMPRESSIVE CLOUD PATTERN TYPE SIGNATURE (APPEARING CYCLONIC TYPE) ALONG WITH NUMEROUS SHOWERS AND EMBEDDED SCATTERED STRONG TSTMS FROM JUST INLAND THE LOUISIANA COAST S TO 27N BETWEEN 89W-93W DUE A MESO-SCALE CONVECTIVE VORTEX (MCV) SPUN OFF BY THE SHORTWAVE TROUGH MOVING THROUGH ERN TEXAS. ANOTHER AREA OF SCATTERED SHOWERS AND TSTMS IS QUICKLY MOVING EWD ACROSS THE ERN PORTION OF THE GULF N OF 26N E OF 86W. UPPER LEVEL MOISTURE FROM THIS ACTIVITY AS SEEN IN THE FORM OF SCATTERED TO BROKEN HIGH LEVEL CLOUDS ON WATER VAPOR IMAGERY IS TRANSLATING EWD ACROSS THE AREA N OF 25N AND E OF 94W. DEBRIS BLOW-OFF HIGH LEVEL CLOUDS FROM WIDESPREAD TSTM ACTIVITY OVER ERN MEXICO IS SPREADING EWD S OF 26N W OF 92W. AT THE SURFACE...THE WRN FRINGE OF WEAK SURFACE RIDGING SUPPORTED BY THE UPPER RIDGE COVERS THE GULF. THIS RIDGE EXTENDS FROM A 1021 MB HIGH OVER THE WRN ATLC. THE WIND FLOW AROUND THE RIDGE IS MAINLY S-SW AT 10-15 KT. SE-S WINDS OF 15 KT ARE ALONG THE TEXAS COAST. MOSTLY CLEAR SKIES ARE EVIDENT OUTSIDE THE PREVIOUSLY MENTIONED CLOUD/CONVECTIVE AREAS. THE SLY FLOW WILL INCREASE OVER THE WRN GULF LATE SUN INTO MON IN ADVANCE OF AN APPROACHING COLD FRONT. CARIBBEAN SEA... ALOFT...MAINLY SW TO W FLOW UNDER MODERATE CONDITIONS COVERS MUCH OF THE WRN AND CENTRAL SECTIONS OF THE SEA. THE ASSOCIATED RATHER TRANQUIL ATMOSPHERIC CONDITIONS CONTINUE...AND ARE EXPECTED TO CHANGE LITTLE OVER THE NEXT 24-48 HRS. A LIGHT SURFACE PRES GRADIENT EXISTS THROUGHOUT INDUCING NE-E TRADE WINDS OF 15-20 KT. WITH THIS WIND FLOW...SCATTERED LOW CLOUDS WITH ISOLATED SHOWERS MOVING WWD ARE SEEN PRIMARILY S OF 18N E OF 81W AND N OF 15N W OF 81W. A STRONGER PRES GRADIENT S OF 15N BETWEEN 72W AND 78W IS RESULTING IN NE-E 20-25 KT WINDS THERE. THE RESULTANT LOW-LEVEL SPEED CONVERGENCE ALONG THE COASTS OF COSTA RICA AND PANAMA IS MATERIALIZING INTO ISOLATED TSTMS ALONG AND JUST INLAND COSTA RICA AND NRN PANAMA. THE NRN CARIBBEAN ISLANDS INCLUDING PUERTO RICO AND HISPANIOLA ARE OBSERVED TO HAVE SCATTERED SHOWERS AND A FEW TSTMS...EXCEPT ACROSS PUERTO RICO WHERE RAINFALL IS MORE WIDESPREAD. LITTLE CHANGE IS EXPECTED OVER THE NEXT COUPLE OF DAYS. ATLANTIC OCEAN... BROAD UPPER LEVEL RIDGING MOVING OFF THE ERN CONUS AND GULF OF MEXICO TO ACROSS THE WRN PORTION OF THE ATLC IS SUPPORTING WEAK SURFACE RIDGING OVER THE WRN PART OF THE AREA. A 1021 MB HIGH CENTER IS NEAR 27N17W...AND IS KEEPING QUIET WEATHER CONDITIONS OVER THIS PORTION OF THE ATLC. THE HIGH WILL SHIFT SE TO 26N64W IN 24 HRS. SCATTERED TO BROKEN HIGH LEVEL CLOUDS ARE NOTED STREAMING EWD FROM THE CONVECTIVE ACTIVITY IN THE ERN GULF OF MEXICO TO OVER THE WRN ATLC REACHING TO 70W. WELL N OF THE AREA...AN UPPER LEVEL TROUGH EXTENDS FROM CANADA SEWD TO NEAR 32N50W. IT SUPPORTS A COLD FRONT THAT HAS JUST DIPPED S INTO THE NRN BOUNDARY OF THE DISCUSSION AREA FROM 32N59W TO 29N65W AND NW TO 31N72W WHERE IT BECOMES A WARM FRONT EXTENDING NW TO INLAND THE SRN PART OF N CAROLINA. ISOLATED SHOWERS ARE POSSIBLE ALONG THE COLD FRONT E OF 65W. OVER THE REMAINDER OF THE AREA...MOSTLY ZONAL UPPER FLOW PREVAILS. A SHORTWAVE RIDGE SHIFTING EWD EXTENDS FROM 32N37W TO 24N43W. AN ASSOCIATED STATIONRY HIGH OF 1022 MB IS AT 29N43W. ONLY SCATTERED TO BROKEN LOW CLOUDS ARE SEEN FROM 24N TO 32N BETWEEN 41W AND 59W. A JET STREAM BRANCH WITH MAXIMUM JET CORE WINDS IN THE RANGE OF 80-95 KT STRETCHES FROM 18N TO 21N BETWEEN 18W AND 64W. TO THE E OF THE SHORTWAVE RIDGE...A SHORTWAVE TROUGH EXTENDS FROM 32N27W SW TO 26N32W. AN ASSOCIATED SURFACE COLD FRONT ENTERS THE DISCUSSION AREA THROUGH 32N30W...AND REACHES SW TO 28N34W WHERE IT TRANSITIONS TO A DISSIPATING STATIONARY FRONT TO 24N44W TO 17N53W. ISOLATED SHOWERS AND WEAK ISOLATED TSTMS ARE WITHIN 45 NM EITHER SIDE THE FRONT. WEAK UPPER LEVEL RIDGING IS ALONG THE COAST OF AFRICA N OF 21N. A 1022 MB HIGH IS E OF THE COLD FRONT AT 25N32W WITH A RIDGE SW TO 9N42W. THIS HIGH WILL DISSIPATE IN 24 HRS. BROAD UPPER LEVEL RIDGING COVERS THE TROPICAL ATLC S OF THE JET STREAM BRANCH. DEEP TROPICAL MOISTURE IS N OF THE ITCZ TO 9N WHERE ISOLATED SHOWERS AND TSTMS ARE NOTED. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ AGUIRRE