000 AXNT20 KNHC 080513 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT FRI SEP 08 2006 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHEASTERN SECTIONS OF SOUTH AMERICA...AND THE 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0345 UTC. ...SPECIAL FEATURE... TROPICAL STORM FLORENCE IS CENTERED NEAR 21.3N 56.1W AT 08/0300 UTC MOVING WEST-NORTHWEST AT 13 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1000 MB. MAXIMUM SUSTAINED WIND SPEED IS 45 KT WITH GUSTS TO 55 KT. SEE THE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT1/WTNT21 KNHC FOR MORE DETAILS. CONDITIONS APPEAR FAVORABLE FOR INTENSIFICATION HOWEVER FLORENCE IS POORLY ORGANIZED AND ELONGATED REMAINING A MINIMAL TROPICAL STORM. CONVECTION IS NOW MAINLY TO THE N OF THE CENTER WITH LITTLE OR NO SHEAR. NUMEROUS STRONG CONVECTION IS WITHIN 60 NM OF LINE 23N54W-21.5N59W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION COVERS THE REMAINDER OF THE AREA FROM 20N-23N BETWEEN 50W-54W AND FROM 20N-26N BETWEEN 54W-60W. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 28W S OF 13N MOVING W 10 KT. LOW AMPLITUDE WAVE THAT IS EMBEDDED WITHIN DRY AIR AND AFRICAN DUST WITH NO ASSOCIATED CONVECTION. TROPICAL WAVE IS ALONG 44W/45W S OF 20N MOVING W 10 KT. WAVE CONTINUES TO BE ENTRAINED INTO TROPICAL STORM FLORENCE. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 90 NM OF LINE 19N40W-22N46W. TROPICAL WAVE IN THE E CARIBBEAN IS ALONG 77W S OF 21N MOVING W 15 KT. LOW LEVEL INVERTED-V SIGNATURE IS OBSERVED ON SATELLITE IMAGERY. CONVECTION IN THE VICINITY IS ASSOCIATED WITH UPPER LEVEL FEATURES. TROPICAL WAVE IN THE W CARIBBEAN IS ALONG 87W/88W S OF 20N MOVING W 10-15 KT. WAVE IS MOSTLY INLAND OVER CENTRAL AMERICA AND ALONG THE COAST OF THE YUCATAN PENINSULA...THUS WAVE POSITION IS BASED ON CONTINUITY. CONVECTION IN THE VICINITY IS ASSOCIATED WITH UPPER LEVEL FEATURES. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 12N14W 10N24W 9N35W 10N50W BECOMING DISTORTED BY TROPICAL STORM FLORENCE THEN ALONG 13N62W 11N78W ACROSS COSTA RICA NEAR 10N83W INTO THE E PACIFIC REGION. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 10N-16N E OF 22W TO THE COAST OF AFRICA AND WITHIN 120/150 NM OF THE AXIS FROM 31W-38W. ...DISCUSSION... GULF OF MEXICO... DEEP LAYERED TROUGH COVERING THE E HALF OF THE US DIPS S OVER THE GULF N OF 23N WITH THE ASSOCIATED NEAR STATIONARY FRONTAL BOUNDARY EXTENDING FROM THE NW ATLC ACROSS NE FLORIDA NEAR 30N84W TO OFF THE COAST OF MEXICO NEAR TUXPAN. BROAD UPPER RIDGE ANCHORED IN THE CARIBBEAN COVERS THE SE GULF AND EXTENDS N OVER THE STRAITS OF FLORIDA. DESPITE THE FRONTAL BOUNDARY...THE GULF REMAINS RATHER SHOWER FREE TONIGHT EXCEPT IN THE FAR NE WITH ISOLATED SHOWERS ARE PRESENT. CARIBBEAN SEA... BROAD UPPER RIDGE COVERS THE CARIBBEAN ANCHORED BY AN UPPER HIGH NEAR THE CAYMAN ISLANDS AND EXTENDS OVER THE SE GULF OF MEXICO AND THE STRAITS OF FLORIDA. A WEAK INVERTED UPPER TROUGH EXTENDS FROM N/CENTRAL VENEZUELA OVER THE E CARIBBEAN IN RESPONSE TO THE BROAD UPPER HIGH OVER THE W TROPICAL ATLC. GENERALLY MOIST CONDITIONS COVER THE CARIBBEAN WITH SOMEWHAT DRIER AIR OVER THE NW SURROUNDING THE UPPER HIGH. SCATTERED SHOWERS/THUNDERSTORMS ARE OVER THE N/CENTRAL CARIBBEAN FROM 16N-19N BETWEEN 66W-79W WITH ISOLATED SHOWERS W OF 86W TO INLAND OVER THE YUCATAN PENINSULA. ATLANTIC OCEAN... BROAD DEEP LAYERED TROUGH OVER THE E US EXTENDS INTO THE FAR NW ATLC N OF 30N W OF 78W. THE ASSOCIATED COLD FRONT EXTENDS THROUGH 32N75W TO 31N79W WHERE IT PULLS UP STATIONARY INTO THE GULF OF MEXICO NEAR JACKSONVILLE FLORIDA. NARROW UPPER RIDGE IS ANCHORED NEAR 30N74W AND EXTENDS S TO CUBA BETWEEN 71W-78W. THIS IS ENHANCING SCATTERED SHOWERS/THUNDERSTORMS N OF 28N W OF 78W TO THE E COAST OF THE FLORIDA PENINSULA AND GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS OVER THE BAHAMA ISLAND CHAIN. THE UPPER LOW IS N OF THE VIRGIN/LEEWARD ISLANDS NEAR 22N64W AND IS PRECEDING FLORENCE IN ITS WESTWARD MOTION WITH THE UPPER TROUGH COVERING THE AREA FROM 60W-68W. AN UPPER HIGH IS CENTERED E OF FLORENCE AND THE TROPICAL WAVE E OF FLORENCE NEAR 20N52W AND COVERS THE TROPICAL ATLC FROM 35W OVER THE LESSER ANTILLES. UPPER TROUGH COVERS THE ATLC NE OF FLORENCE N OF 22N FROM 25W-40W WITH THE UPPER LOW CENTERED NEAR 29N30W. THIS IS ENHANCING CONVECTION ASSOCIATED WITH THE TROPICAL WAVE E OF FLORENCE. AT THE SURFACE HOWEVER...BROAD RIDGE DOMINATES MOST OF THE ATLC WITH IT WEAKENING OVER THE CENTRAL ATLC DUE TO THE PRESENCE OF FLORENCE. $$ WALLACE