000 AXNT20 KNHC 060020 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT THU SEP 05 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...SPECIAL FEATURES... THE CENTER OF TROPICAL DEPRESSION GABRIELLE AT 05/2100 UTC IS NEAR 18.2N 68.6W. THIS POSITION IS ABOUT 30 MI...50 KM SSW OF PUNTA CANA DOMINICAN REPUBLIC. GABRIELLE IS MOVING NORTHWESTWARD AT 8 KNOTS. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 1010 MB. THE MAXIMUM SUSTAINED WIND SPEEDS ARE 25 KNOTS WITH GUSTS TO 35 KNOTS. PUBLIC ADVISORIES ON GABRIELLE ARE ISSUED UNDER WMO HEADER WTNT32 KNHC AND UNDER AWIPS HEADER MIATCPAT2...AND FORECAST/ADVISORIES ARE ISSUED UNDER WMO HEADER WTNT22 KNHC AND UNDER AWIPS HEADER MIATCMAT2. GABRIELLE IS EXPECTED TO DEGENERATE INTO A REMNANT LOW PRESSURE AREA TONIGHT OR FRIDAY AS THE CENTER PASSES NEAR OR OVER THE EASTERN DOMINICAN REPUBLIC. GABRIELLE IS EXPECTED TO PRODUCE TOTAL RAINFALL AMOUNTS OF 2 TO 4 INCHES OVER PUERTO RICO AND THE U.S. VIRGIN ISLANDS...WITH ISOLATED MAXIMUM AMOUNTS OF UP TO 8 INCHES POSSIBLE IN AREAS OF MOUNTAINOUS TERRAIN. THESE RAINS COULD CAUSE DANGEROUS FLASH FLOODS AND MUD SLIDES OVER MOUNTAINOUS TERRAIN. PRESENTLY CLUSTERS OF SCATTERED MODERATE TO STRONG CONVECTION ARE OVER HISPANIOLA...PUERTO RICO...AND THE VIRGIN ISLANDS FROM 16N-20N BETWEEN 65W-72W. A 1011 MB LOW IS NEAR 22N95W IN THE SOUTHWESTERN CORNER OF THE GULF OF MEXICO. A SURFACE TROUGH EXTENDS FROM 26N96W TO THE LOW CENTER TO 17N93W. SOME DEVELOPMENT OF THIS SYSTEM IS STILL POSSIBLE...AND A TROPICAL DEPRESSION COULD FORM BEFORE THE LOW MOVES INLAND ALONG THE COAST OF MEXICO ON FRIDAY. THIS SYSTEM HAS A MEDIUM CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS...AND A MEDIUM CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 5 DAYS. REGARDLESS OF TROPICAL CYCLONE FORMATION...HEAVY RAIN AND GUSTY WINDS WILL BE POSSIBLE ALONG THE COAST OF THE MEXICAN STATES OF VERACRUZ AND TAMAULIPAS THROUGH FRIDAY. PRESENTLY CLUSTERS OF SCATTERED MODERATE CONVECTION ARE OVER THE W GULF W OF 90W. ...TROPICAL WAVES... AN ATLANTIC OCEAN TROPICAL WAVE EXTENDS FROM 20N30W TO A 1011 MB LOW AT 13N31W TO 8N32W MOVING W AT 10 KT. DEVELOPMENT IS EXPECTED TO BE LIMITED DUE TO DRY AIR...AND ENVIRONMENTAL CONDITIONS ARE FORECAST TO BECOME UNFAVORABLE IN A COUPLE OF DAYS. THIS SYSTEM HAS A LOW CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS. PRESENTLY SCATTERED SHOWERS ARE WITHIN 120 NM OF THE WAVE AXIS. AN ATLANTIC OCEAN TROPICAL WAVE EXTENDS FROM 20N55W TO 14N53W TO 10N50W MOVING W AT 15 KT. PRESENTLY SCATTERED SHOWERS ARE WITHIN 120 NM OF THE WAVE AXIS. A W CARIBBEAN SEA TROPICAL WAVE IS EXTENDS FROM 18N81W TO 10N81W MOVING W AT 10 KT. PRESENTLY SCATTERED SHOWERS ARE WITHIN 120 NM OF THE WAVE AXIS. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH PASSES THROUGH COASTAL GUINEA-BISSAU NEAR 12N16W TO 13N31W TO 8N40W. THE ITCZ CONTINUES FROM 8N40W TO 7N44W TO 8N48W. SCATTERED MODERATE CONVECTION IS FROM 7N-12N BETWEEN 18W-22W. ...DISCUSSION... THE GULF OF MEXICO... A SURFACE LOW AND TROUGH IS OVER THE W GULF OF MEXICO. PRESENTLY CLUSTERS OF SCATTERED MODERATE CONVECTION ARE OVER THE W GULF W OF 90W. SEE ABOVE. A STATIONARY FRONT IS OVER THE N GULF STATES E OF E TEXAS. SCATTERED MODERATE CONVECTION IS INLAND FROM 29N- 31N E OF 98W. MORE SCATTERED MODERATE CONVECTION IS INLAND OVER FLORIDA...W CUBA...AND THE YUCATAN PENINSULA. SCATTERED MODERATE CONVECTION IS ALSO OVER THE YUCATAN CHANNEL. IN THE UPPER LEVELS...UPPER LEVEL RIDGING IS OVER THE W GULF. THE BASE OF AN UPPER LEVEL TROUGH IS OVER N FLORIDA. CONSIDERABLE UPPER LEVEL MOISTURE IS NOTED OVER THE ENTIRE GULF. EXPECT THE W GULF SYSTEM TO BE THE DOMINATE CONCERN OVER THE NEXT 24 HOURS. THE CARIBBEAN SEA... T.D.GABRIELLE IS ON THE COAST OF THE DOMINICAN REPUBLIC. SEE ABOVE. A SURFACE TROUGH IS NE OF GABRIELLE FROM 24N64W TO 20N68W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS E OF THE TROUGH AXIS FROM 16N-24N BETWEEN 60W-64W TO INCLUDE PORTIONS OF THE LEEWARD ISLANDS. A TROPICAL WAVE IS OVER THE W CARIBBEAN WITH SHOWERS. SEE ABOVE. ISOLATED MODERATE CONVECTION IS OVER CENTRAL AMERICA FROM NICARAGUA TO THE YUCATAN PENINSULA. A MONSOON TROUGH EXTENDS FRO N COLOMBIA TO COSTA RICA. ISOLATED MODERATE CONVECTION IS S OF 10N BETWEEN 77W-84W. SCATTERED MODERATE CONVECTION IS OVER N COLOMBIA AND NW VENEZUELA FROM 9N- 13N BETWEEN 70W-75W. IN THE UPPER LEVELS AN UPPER LEVEL HIGH IS CENTERED OVER THE E CARIBBEAN NEAR PUERTO RICO. HISPANIOLA... PLEASE READ THE NHC ADVISORIES AND LOCAL AND NATIONAL ADVISORIES FOR WATCH AND WARNING INFORMATION FOR THE DOMINICAN REPUBLIC... WITH RESPECT TO T.D. GABRIELLE. THE ATLANTIC OCEAN... A SURFACE TROUGH IS NE OF GABRIELLE FROM 24N64W TO 20N68W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS E OF THE TROUGH AXIS FROM 16N-24N BETWEEN 60W-64W. ANY DEVELOPMENT OF THIS TROUGH DURING THE NEXT COUPLE OF DAYS IS EXPECTED TO BE SLOW DUE TO STRONG UPPER-LEVEL WINDS...AND THIS SYSTEM HAS A LOW CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS AS IT MOVES NORTHWESTWARD AT 10 TO 15 MPH. SOME DEVELOPMENT OF THIS SYSTEM COULD ALSO OCCUR IN A FEW DAYS WHEN IT INTERACTS WITH TROPICAL DEPRESSION GABRIELLE OR ITS REMNANTS AND MOVES NORTHEASTWARD AHEAD OF A COLD FRONT OVER THE CENTRAL ATLANTIC OCEAN. THIS SYSTEM HAS A MEDIUM CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 5 DAYS. A 1024 HIGH IS CENTERED OVER THE CENTRAL ATLANTIC NEAR 33N47W. AN UPPER LEVEL LOW IS CENTERED NEAR 30N60W PRODUCING SCATTERED MODERATE CONVECTION FROM 28N-32N BETWEEN 53W-62W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORMOSA