000 AXNT20 KNHC 190005 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT FRI APR 18 2014 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. ...SPECIAL FEATURE... A GALE WARNING REMAINS IN EFFECT FOR THE NE GULF IN ASSOCIATION WITH A DEEPENING AREA OF LOW PRES LOCATED NEAR 29N85W AT 2100 UTC. THE LOW WILL SHIFT SLOWLY NE...MOVING INLAND ACROSS THE CENTRAL FLORIDA PANHANDLE TONIGHT...THEN WILL CONTINUE NE TO EXIT THE GEORGIA COAST SAT AFTERNOON. GALE WINDS AT THE GULF ARE EXPECTED SUBSIDE LATER TONIGHT. PLEASE SEE THE HIGH SEAS FORECAST UNDER AWIPS/WMO HEADERS MIAHSFAT2/ FZNT02 KNHC. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE TROPICAL ATLC NEAR 14N16W AND CONTINUES ALONG 09N19W TO 04N21W. THE ITCZ BEGINS NEAR 04N21W AND CONTINUES ALONG 01N30W 01S40W TO THE NORTHERN COAST OF BRAZIL NEAR 01S45W. CLUSTERS OF MODERATE TO ISOLATED STRONG CONVECTION ARE N OF 02N BETWEEN 07W-12W. ISOLATED SHOWERS ARE ELSEWHERE FROM 02N-05N BETWEEN 18W- 24W...05S-01N BETWEEN 26W-30W AND FROM 02S-03N W OF 35W. ...DISCUSSION... GULF OF MEXICO... A DEEP LAYER TROUGH EXTENDING FROM THE GREAT LAKES ALONG THE EASTERN CONUS WITH A BASE INTO THE EASTERN GULF SUPPORTS A FRONTAL SYSTEM THAT EXTENDS FROM A 1011 MB LOW S OF PANAMA CITY NEAR 29N85W. A COLD FRONT EXTENDS FROM THE LOW ALONG 25N85W 22N88W TO 21N91W WHERE IT TRANSITIONS INTO A SURFACE TROUGH TO 18N94W. A PARTIAL STATIONARY FRONT DEPARTS FROM THE LOW NE ACROSS THE CENTRAL FLORIDA PANHANDLE AND THEN INTO GEORGIA WHERE IT TRANSITIONS INTO A WARM FRONT. THERE ARE GALE FORCE WINDS AT THE W-NW QUADRANTS OF THE LOW CENTER WHICH ARE EXPECTED TO SUBSIDE LATER TONIGHT. PLEASE SEE SPECIAL FEATURE SECTION. THE TROUGH ALOFT CONTINUES TO AMPLIFY AN UPPER RIDGE NOW ACROSS THE WESTERN ATLC THUS INDUCING DIFFLUENT FLOW TO SUPPORT SCATTERED MODERATE CONVECTION AND ISOLATED TSTMS E OF 86W...INCLUDING THE FLORIDA PENINSULA. THE LOW WILL SHIFT SLOWLY NE...MOVING INLAND ACROSS THE CENTRAL FLORIDA PANHANDLE TONIGHT...THEN WILL CONTINUE NE TO EXIT THE GEORGIA COAST SAT AFTERNOON. THE ASSOCIATED COLD FRONT WILL MOVE ACROSS THE FLORIDA PENINSULA TONIGHT INTO SAT MORNING. IN ITS WAKE...A RIDGE WILL THEN EXTEND ACROSS THE GULF THROUGH THE REMAINDER WEEKEND. CARIBBEAN SEA... MIDDLE TO UPPER LEVEL RIDGING COVERS MUCH OF THE BASIN WITH WATER VAPOR IMAGERY SHOWING DRY AIR SUBSIDENCE. THIS PATTERN ALOFT IS PROVIDING OVERALL STABILITY ACROSS THE BASIN. A BROAD SURFACE RIDGE COVERING THE CENTRAL AND SW N ATLC EXTENDS INTO THE NORTHERN BASIN CREATING A TIGHTER PRESSURE GRADIENT TO SUPPORT WINDS OF 20 KT ACROSS THE CENTRAL AND EASTERN BASIN. A RELAXED PRESSURE GRADIENT OVER THE NW CARIBBEAN SEA SUPPORT LIGHTER WINDS RANGING FROM 5-15 KT. THE MOIST AIRMASS FORMERLY GENERATING SHOWERS ACROSS PUERTO RICO HAS MOVED INTO HISPANIOLA AND NOW SUPPORT SHOWERS AND TSTMS THERE. CURRENTLY SATELLITE IMAGERY SHOW THESE SHOWERS ARE CONCENTRATED OVER CENTRAL-WESTERN DOMINICAN REPUBLIC AND HAITI. A LINE OF SHOWERS AND TSTMS IS ALONG CUBA BEING ENHANCED BY LOW LEVEL MOISTURE CONVERGENCE. THE HIGH PRES IS FORECAST TO MOVE SOUTH DURING THE NEXT 24 HOURS. THIS PATTERN WILL MAINTAIN FRESH TO LOCALLY STRONG TRADES NEAR THE COAST OF COLOMBIA WITH MODERATE TO LOCALLY FRESH TRADES ELSEWHERE THROUGH SAT...WITH WINDS THEN WEAKENING SUN AS LOW PRES MOVES N OF AREA AND THE HIGH PRES WEAKENS. A COLD FRONT EXITING THE GULF SAT MORNING IS EXPECTED TO SUPPORT SHOWERS OVER THE NW CARIBBEAN OVER THE WEEKEND. ...HISPANIOLA... A LOW LEVEL MOIST AIRMASS PREVIOUSLY GENERATING SHOWERS ACROSS PUERTO RICO HAS MOVED INTO HISPANIOLA AND ADJACENT WATERS TO SUPPORT SHOWERS AND TSTMS CURRENTLY CONCENTRATED OVER CENTRAL- WESTERN DOMINICAN REPUBLIC AND HAITI. A COLD FRONT MOVING OFF THE GULF WATERS ON SAT MORNING WILL ADVECT MOISTURE INTO THE REGION THUS INCREASING THE CHANCES OF RAIN SUN INTO MONDAY. ATLANTIC OCEAN... A BROAD SURFACE RIDGE ANCHORED BY A 1032 MB HIGH NEAR 34N54W COVERS THE CENTRAL AND SW N ATLC BEING SUPPORTED BY A BROAD RIDGE ALOFT. SCATTERED SHOWERS AND ISOLATED TSTMS ARE OVER THE SW N ATLC N OF 25N W OF 76W ASSOCIATED WITH A FRONTAL SYSTEM CURRENTLY ANALYZED OVER THE EASTERN GULF OF MEXICO. A ZONE OF DIFFLUENT FLOW ALOFT BETWEEN THE TROUGH SUPPORTING THE FRONT AND THE RIDGE OVER THE W ATLC SUPPORTS THIS CONVECTION. OTHERWISE OVER THE EASTERN ATLC...A SURFACE TROUGH EXTENDS FROM 30N26W TO 25N32W WITH NO CONVECTION ASSOCIATED WITH IT. FARTHER EAST...A WEAK 1018 MB HIGH IS SITUATED NEAR 29N17W WHICH IS EXPECTED TO DISSIPATE LATER TONIGHT. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ NR