000 AXNT20 KNHC 312358 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT THU JUL 31 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 2315 UTC. ...SPECIAL FEATURES... A 1007 MB LOW CENTERED NEAR 11N53W...OR 500 NM E OF THE WINDWARD ISLANDS...IS MOVING W-NW 15 KT. A HURRICANE HUNTER AIRCRAFT MEASURED 40 KT GALE FORCE WINDS OVER THE NORTHERN PORTION OF THE LOW. THE LOW PRESENTLY LACKS DEEP CONVECTION NEAR THE CENTER THUS WAS NOT NAMED A TROPICAL CYCLONE. ONLY A SMALL 15 NM RADIUS AREA OF SCATTERED MODERATE CONVECTION IS NOW 90 NM E OF THE CENTER. DRY SAHARAN DUST IS NOTED NEAR THE LOW CENTER. THE LOW DOES HAVE HOWEVER A HIGH CHANCE OF TROPICAL FORMATION WITHIN 48 HOURS. REGARDLESS OF DEVELOPMENT GALE FORCE WINDS ARE LIKELY TO SPREAD ACROSS PORTIONS OF THE LESSER ANTILLES BEGINNING EARLY FRIDAY. PLEASE SEE THE LATEST NHC TROPICAL WEATHER OUTLOOK UNDER AWIPS/WMO HEADERS MIATWOAT/ABNT20 KNHC FOR MORE DETAILS. ...TROPICAL WAVES... A TROPICAL WAVE EXTENDS FROM 18N33W TO 9N29W MOVING W AT 10 KT. A 1010 MB LOW IS LOCATED ON THE BASE OF THE WAVE AXIS AT 10N32W. A MOIST AREA IS NOTED ON THE SSMI TOTAL PRECIPITABLE WATER VAPOR IMAGERY. A DRY SAHARAN AIR LAYER IS N AND W OF THE TROPICAL WAVE. A SMALL 30 NM RADIUS AREA OF SCATTERED MODERATE CONVECTION IS NOW 120 NM SE OF THE CENTER. A TROPICAL WAVE IS JUST E OF THE LESSER ANTILLES EXTENDS FROM 18N60W TO 10N58W AND MOVING W AT 15-20 KT. THE WAVE REMAINS TO THE W-NW OF THE 1007 MB GALE LOW DISCUSSED IN THE SPECIAL FEATURES SECTION. A MOIST AREA IS NOTED ON THE SSMI TOTAL PRECIPITABLE WATER VAPOR IMAGERY. A DRY SAHARAN AIR LAYER IS N OF 18N AND E OF THE TROPICAL WAVE. SCATTERED SHOWERS ARE FROM 10N-17N BETWEEN 60W-62W. ...ITCZ/MONSOON TROUGH... MONSOON TROUGH EXTENDS FROM THE COAST OF WEST AFRICA AT 20N16W TO AN EMBEDDED 1012 MB LOW AT 19N19W TO 13N18W TO 11N22W TO 10N32W TO 4N38W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 4N38W TO 5N46W TO 9N51W. BESIDES THE CONVECTION MENTIONED WITH THE TROPICAL WAVES AND SPECIAL FEATURE LOW...SCATTERED MODERATE CONVECTION IS FROM 5N-8N BETWEEN 31W-36W. ...DISCUSSION... GULF OF MEXICO... AS OF 2100 UTC...A QUASI-STATIONARY FRONT EXTENDS FROM N FLORIDA AT 30N82W TO S FLORIDA AT 26N82W TO THE CENTRAL GULF OF MEXICO NEAR 25N90W. SCATTERED MODERATE CONVECTION IS OVER CENTRAL AND S FLORIDA S OF 28N. AIR MASS ISOLATED MODERATE CONVECTION IS NOTED OVER W CUBA...AND N YUCATAN PENINSULA. SCATTERED SHOWERS ARE OVER THE SE GULF FROM 23N-26N BETWEEN 83W-88W. SCATTERED MODERATE CONVECTION IS ALSO ALONG THE TEXAS COAST S OF HOUSTON. MOSTLY FAIR WEATHER IS OVER THE REMAINDER OF THE GULF. IN THE UPPER LEVELS...UPPER LEVEL RIDGING EXTENDS FROM CENTRAL TEXAS TO CENTRAL FLORIDA. UPPER LEVEL MOISTURE IS ABOVE THE STATIONARY FRONT...AND OVER THE NORTH GULF STATES. STRONG SUBSIDENCE IS ELSEWHERE. EXPECT OVER THE NEXT 24 HOURS FOR THE FRONT TO DISSIPATE. AREA OF CONVECTION IS EXPECTED TO PERSIST OVER THE SE GULF HOWEVER. CARIBBEAN SEA... A TROPICAL WAVE IS JUST E OF THE LESSER ANTILLES. SEE ABOVE. 10- 25 KT TRADEWINDS ARE OVER THE CARIBBEAN SEA WITH STRONGEST WINDS ALONG THE COAST OF N COLOMBIA. AIR MASS SCATTERED MODERATE CONVECTION IS NOTED OVER N COLOMBIA...PANAMA...COSTA RICA...E HONDURAS...AND GUATEMALA. MORE SCATTERED MODERATE CONVECTION IS OVER E CUBA...JAMAICA...HISPANIOLA...AND PUERTO RICO. IN THE UPPER LEVELS... A SMALL UPPER LEVEL LOW IS CENTERED N OF HONDURAS NEAR 17N86W. AN UPPER LEVEL HIGH IS CENTERED N OF VENEZUELA NEAR 12N65W. EXPECT OVER THE NEXT 24 HOURS FOR CONVECTION TO BE OVER THE LESSER ANTILLES...AND THE SW CARIBBEAN. ALSO EXPECT MORE AIRMASS CONVECTION FRI AFTERNOON AND EVENING. ...HISPANIOLA... PRESENTLY SCATTERED MODERATE CONVECTION IS INLAND OVER HISPANIOLA FROM 18N-20N BETWEEN 69W-73W. MORE AIR MASS AFTERNOON SHOWERS OR CONVECTION ARE EXPECTED FRI. ATLANTIC OCEAN... SCATTERED SHOWERS ARE OVER THE W ATLANTIC AND N BAHAMAS FROM 27N- 32N BETWEEN 77W-80W. A 1014 MB LOW IS CENTERED OVER THE CENTRAL ATLANTIC NEAR 29N49W. A SURFACE TROUGH EXTENDS SW FROM THE LOW TO 26N48W TO 28N55W. SCATTERED SHOWERS ARE WITHIN 90 NM OF THE LOW AND TROUGH. OF NOTE IN THE UPPER LEVELS...AN UPPER LEVEL LOW IS CENTERED OVER THE W ATLANTIC NEAR 26N64W. SCATTERED SHOWERS ARE FROM 20N-27N BETWEEN 65W-70W. ANOTHER UPPER LEVEL LOW IS CENTERED NEAR 31N50N ENHANCING SHOWERS OVER THE SURFACE TROUGH. EXPECT OVER THE NEXT 24 HOURS FOR THE WESTERN UPPER LEVEL LOW TO REMAIN QUASI-STATIONARY WITH SHOWERS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORMOSA