000 AXNT20 KNHC 282358 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT FRI SEP 28 2007 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHERN 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...METEOROLOGICAL ANALYSIS... WEATHER OBSERVATIONS...AND RADAR. BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...SPECIAL FEATURES... KAREN IS WEAKENING UNDER STRONG UPPER LEVEL SOUTHWESTERLY FLOW BUT IS STILL A MINIMAL TROPICAL STORM OVER THE OPEN WATERS OF THE CENTRAL ATLANTIC. AT 28/2100 UTC KAREN WAS NEAR 16.4N 49.9W OR ABOUT 675 NM EAST-NORTHEAST OF THE WINDWARD ISLANDS...MOVING NORTHWEST NEAR 10 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1008 MB. MAXIMUM SUSTAINED WINDS ARE 35 KT WITH GUSTS TO 45 KT. SEE LATEST NHC FORECAST ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT2/WTNT22 KNHC AND THE PUBLIC ADVISORY UNDER MIATCPAT2/WTNT32 KNHC FOR MORE DETAILS. KAREN IS ATTEMPTING TO MAKE A COMEBACK. DEEP CONVECTION IS DEVELOPING AGAIN E OF THE CENTER. NUMEROUS MODERATE TO SCATTERED STRONG CONVECTION IS FROM 14N-18N BETWEEN 45W-50W. A GRADUAL WEAKENING IS FORECAST FOR THE NEXT FEW DAYS DUE TO AN UNFAVORABLE UPPER WIND ENVIRONMENT.. HURRICANE LORENZO MADE LANDFALL EARLY THIS MORNING ALONG THE EAST-CENTRAL COAST OF MEXICO AS A CATEGORY ONE HURRICANE ON THE SAFFIR-SIMPSON SCALE WITH MAXIMUM SUSTAINED WINDS OF 70 KT. THIS EVENING LORENZO IS DISSIPATING OVER CENTRAL MEXICO. AT 28/2100 TROPICAL DEPRESSION LORENZO WAS LOCATED NEAR LATITUDE 20.8 NORTH...LONGITUDE 99.0 WEST OR ABOUT 90 NM...170 KM...WEST OF TUXPAN MEXICO...MOVING WEST-NORTHWEST NEAR 8 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1008 MB. MAXIMUM SUSTAINED WIND SPEED IS 20 KT GUSTS 25 KT. AT THIS TIME...THE NHC ISSUED THE LAST ADVISORY ON THIS SYSTEM. LORENZO IS EXPECTED TO PRODUCE ADDITIONAL RAINFALL ACCUMULATIONS OF 4 TO 7 INCHES OVER EAST CENTRAL MEXICO. ISOLATED MAXIMUM STORM TOTALS OF 15 INCHES ARE POSSIBLE. THESE RAINS COULD CAUSE LIFE-THREATENING FLASH FLOODS AND MUD SLIDES. THIS MORNING...SATELLITE IMAGERY...MICROWAVE DATA AND SHIP OBSERVATIONS INDICATED THAT THE AREA OF LOW PRESSURE ASSOCIATED WITH A TROPICAL WAVE LOCATED NEAR THE CAPE VERDE ISLANDS DEVELOPED INTO TROPICAL DEPRESSION FOURTEEN. AT 28/2100 UTC THIS TROPICAL CYCLONE WAS NEAR 14.0N 27.0W OR ABOUT 215 NM...390 KM...SOUTHWEST OF THE CAPE VERDE ISLANDS MOVING WEST NEAR 4 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1008 MB. MAXIMUM SUSTAINED WINDS ARE 30 KT WITH GUSTS TO 40 KT. SEE LATEST NHC FORECAST ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT4/WTNT24 KNHC AND THE PUBLIC ADVISORY UNDER MIATCPAT4/WTNT34 KNHC FOR MORE DETAILS. THE CLOUD PATTERN HAS NOT BECOME ANY BETTER ORGANIZED SINCE EARLIER TODAY. THERE ARE PATCHES OF DEEP CONVECTION WITHIN 175 NM E OF CENTER FROM 13N-15N. ...TROPICAL WAVES... A TROPICAL WAVE IS BETWEEN T.D. FOURTEEN AND T.S. KAREN ALONG 33W SOUTH OF 20W MOVING W 10-15 KT. THE WAVE SHOWS UP IN LOW LEVEL SATELLITE DERIVED WINDS AND VORTICITY...AND THE UW CIMSS TPW PRODUCTS WITH A LOW AMPLITUDE MOISTURE SURGE. SCATTERED MODERATE CONVECTION IS NEAR THE INTERSECTION OF THE WAVE AND THE ITCZ. A TROPICAL WAVE IS OVER THE CARIBBEAN ALONG 78W/79W S OF 21N MOVING W NEAR 10-15 KT. AN AREA OF SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS JUST AHEAD OF THE WAVE AXIS AFFECTING THE SW CARIBBEAN AND THE CARIBBEAN PLAINS OF NICARAGUA. THE WAVE IS ALSO ENHANCING SCATTRED SHOWERS AND TSTMS OVER EASTERN CUBA AND JAMAICA. MOISTURE FROM THIS WAVE WILL CONTINUE TO AFFECT CUBA AND CENTRAL AMERICA TONIGHT AND TOMORROW. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 8N13W 12N24W 10N36W 12N47W 9N60W. BESIDES THE CONVECTION MENTIONED ABOVE WITH TROPICAL CYCLONES AND THE TROPICAL WAVE OVER THE EASTERN ATLC...SCATTERED MODERATE CONVECTION IS FROM 4N-11N EAST OF 17W TO THE COAST OF W AFRICA. SIMILAR CONVECTION IS FOUND OVER PARTS OF GUYANA AND NE VENEZUELA. DISCUSSION... GULF OF MEXICO... A COLD FRONT IS JUST ENTERING THE NORTHERN GULF WATERS. AS OF 2100Z...THE FRONTAL BOUNDARY EXTENDS FROM THE FLORIDA PANHANDLE THROUGH SE LOUISIANA TO THE NW GULF/MIDDLE TEXAS COAST. THE FRONT IS FORECAST TO MOVE ACROSS THE GULF REACHING SOUTH-CENTRAL FLORIDA EARLY SAT MORNING AND MOVING ACROSS SOUTH FLORIDA BY SAT AFTERNOON. A HIGH PRESS RIDGE WILL BUILD IN BEHIND THE FRONT INCREASING WINDS AND SEAS ACROSS THE GULF ON SUNDAY. ON THIS DAY...THE GFS COMPUTER MODEL SHOWS ELY WINDS OF 20 TO 25 KT OVER THE NE QUADRANT OF THE GULF. A SFC TROUGH IS ANALYZED OVER THE FAR WEST GULF ALONG 95W/96W. FLOW AROUND THE CIRCULATION OF T.D. LORENZO COUPLED WITH THIS SFC TROUGH IS GENERATING SCATTERED SHOWERS AMD TSTMS OVER THE WESTERN GULF MAINLY BETWEEN 22N-27N WEST OF 90W. DRY AIR IS INVADING THE NORTHERN GULF WATERS. DIFFLUENCE ASSOCIATED WITH AN UPPER HIGH LOCATED NEAR 22N95W IS ALSO SUPPORTING THIS CONVECTIVE ACTIVITY. A RIDGE EXTENDS EWD FROM THIS HIGH COVERING SOUTH FLORIDA...WESTERN CUBA AND THE YUCATAN PENINSULA WITH MID/UPPER DRY AIR. CARIBBEAN SEA... A TROPICAL WAVE IS MOVING WWD ACROSS THE WEST-CENTRAL CARIBBEAN INCREASING SHOWER AND TSTM ACTIVITY. SEE TROPICAL WAVE SECTION. ALOFT...AN UPPER-LEVEL TROUGH REMAINS OVER THE NW CARIBBEAN. UPPER DIFFLUENCE BETWEEN THIS TROUGH AND AN UPPER RIDGE OVER THE CENTRAL CARIBBEAN...JUST SOUTH OF HISPANIOLA IS SUPPORTING THE AREA OF SHOWERS AND TSTMS LOCATED JUST AHEAD OF THE AFOREMENTIONED TROPICAL WAVE. SIMILAR ACTIVITY IS OVER HONDURAS NEAR THE BASE OF THE UPPER-LEVEL TROUGH. TRADE WINDS REMAIN LIGHT TO MODERATE ACROSS THE BASIN...BUT WINDS/SEAS COULD BE HIGHER AT TIMES NEAR SQUALLS ASSOCIATED WITH THE TROPICAL WAVE. NWLY UPPER WINDS ASSOCIATED WITH AN UPPER LOW LOCATED OVER THE CENTRAL ATLC ARE ADVECTING HIGH CLOUDS/MID TO UPPER LEVEL MOISTURE OVER PUERTO RICO AND THE NE CARIBBEAN INTO THE LESSER ANTILLES. THESE WINDS...COMBINED WITH THE LOCAL EFFECTS ARE ALSO HELPING TO INDUCE SCATTERED TO NUMEROUS SHOWERS AND TSTMS OVER HISPANIOLA AND PUERTO RICO...PARTICULAR DURING THE AFTERNOON AND EARLY EVENING HOURS. ATLANTIC OCEAN... A DEEP LAYER TROUGH REMAINS E OF THE FLORIDA PENINSULA. A TROUGH OF LOW PRESSURE LIES ALONG 31N77W THROUGH THE NW BAHAMAS TO CENTRAL CUBA. THE 1014 MB SFC LOW LOCATED ALONG THIS TROUGH WAS DROPPED ON THE 2100 Z SFC MAP BASE ON SFC DATA AND VIS SATELLITE IMAGERY. THE CU LINES ARE NOW VERY LINEAR OVER THE AREA... INDICATING THAT THE LOW IS NO LONGER IDENTIFIABLE. LIGHTNING DATA DEPICTS MOST OF THE TSTMS ACTIVITY WITHIN 130 NM AHEAD OF THE SFC TROUGH AFFECTING THE W ATLC WEST OF 73W. THE REMAINDER OF THE ATLC IS CURRENTLY UNDER THE INFLUENCE OF A SFC RIDGE ANCHORED ON A 1024 HIGH LOCATED NEAR 36N54W. A WEAK 1019 SFC HIGH IS NEAR 27N28W. IN THE UPPER LEVELS...N OF 20 N...A BROAD UPPER TROUGH EXTENDS FROM THE CANARY ISLANDS TO A LARGE UPPER LOW LOCATED NEAR 26N60W. THIS FEATURE IS STILL PRODUCING SOME CLOUDINESS WITH ISOLATED SHOWERS FROM 21N-28N BETWEEN 47W-62W. S OF 20N...A LARGE UPPER LEVEL HIGH IS OVER THE TROPICS NEAR 11N35W. $$ GR