000 AXNT20 KNHC 060555 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 105 AM EST THU NOV 06 2008 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...METEOROLOGICAL ANALYSIS...WEATHER OBSERVATIONS...AND RADAR. BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0515 UTC. ...SPECIAL FEATURE... THE CENTER OF TROPICAL DEPRESSION SEVENTEEN AT 06/0600 UTC IS NEAR 14.6N 82.1W OR ABOUT 75 NM EAST-SOUTHEAST OF CABO GRACIAS A DIOS ON THE NICARAGUA/HONDURAS BORDER. TROPICAL DEPRESSION SEVENTEEN IS MOVING NORTHWEST AT 4 KT. THE MINIMUM CENTRAL PRESSURE REPORTED BY THE HURRICANE HUNTER IS 1004 MB. MAXIMUM SUSTAINED WIND SPEED IS 30 KT WITH GUSTS TO 40 KT. PLEASE SEE THE LATEST NHC INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT2/WTNT32 KNHC AND THE FULL FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT2/WTNT22 KNHC FOR MORE DETAILS. THE DEPRESSION IS EXPECTED TO BECOME A TROPICAL STORM TODAY...AND ADDITIONAL STRENGTHENING IS FORECAST THROUGH FRIDAY...WITH A GRADUAL TURN TOWARD THE NORTH FORECAST ON FRIDAY. THE DEPRESSION IS EXPECTED TO PRODUCE 2 TO 3 INCHES OF RAIN OVER EASTERN HONDURAS AND NORTHEASTERN NICARAGUA WITH ISOLATED MAXIMUM TOTALS OF 6 INCHES POSSIBLE. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS OVER THE W CARIBBEAN FROM 12N-21N BETWEEN 75W-85W...AFFECTING PORTIONS OF E CUBA...E HONDURAS...AND NE NICARAGUA. ...THE ITCZ... ITCZ AXIS IS ANALYZED ALONG 9N13W 7N22W 6N34W 7N44W 6N59W. SCATTERED MODERATE CONVECTION IS FROM 2N-6N BETWEEN 13W-18W. ISOLATED MODERATE CONVECTION IS S OF 10N BETWEEN 23W-30W. SCATTERED MODERATE CONVECTION IS FROM 7N-12N BETWEEN 31W-38W. THESE AREAS OF CONVECTION ARE BEING ENHANCED BY UPPER LEVEL DIVERGENCE. ...DISCUSSION... GULF OF MEXICO... SOUTHWESTERLY FLOW ALOFT COVERS MUCH OF THE GULF REGION...AS A DEEP TROUGH OVER THE CENTRAL PLAINS OF THE CONUS ADVANCES EASTWARD IN THE WAKE OF A DEPARTING UPPER RIDGE. SUBSIDENCE IS OCCURRING IN ASSOCIATION WITH A SURFACE RIDGE OF HIGH PRESSURE OVER THE SE CONUS THAT EXTENDS INTO THE GULF. THIS SURFACE RIDGE IS ANCHORED BY A 1018 MB SURFACE HIGH OVER ALABAMA NEAR 32N87W. ADDITIONALLY...DEEP LAYER DRY AIR IS PRESENT ACROSS MUCH OF THE GULF REGION...WHERE STABLE ATMOSPHERIC CONDITIONS PERSIST. THE COMBINATION OF THE SUBSIDENCE AND DEEP LAYER DRY AIR IS MAINTAINING GENERALLY FAIR WEATHER CONDITIONS ACROSS THE GULF REGION. CARIBBEAN SEA... TROPICAL DEPRESSION SEVENTEEN IS OVER THE W CARIBBEAN. PLEASE SEE THE SPECIAL FEATURE SECTION ABOVE FOR MORE INFORMATION ON THIS SYSTEM. AN UPPER LEVEL HIGH IS OVER THE CENTRAL CARIBBEAN NEAR 15N73W...WITH THE ANTICYCLONIC FLOW AROUND THE HIGH COVERING MUCH OF THE CARIBBEAN. TO THE W OF THE HIGH...DEEP LAYER MOISTURE AND UPPER LEVEL DIVERGENCE ARE PRESENT OVER PORTIONS OF THE W CARIBBEAN...WHERE TROPICAL DEPRESSION SEVENTEEN IS ALSO PRESENT. FARTHER TO THE E...DEEP LAYER DRY AIR E OF THE UPPER HIGH IS RESULTING IN GENERALLY FAIR WEATHER CONDITIONS ACROSS MUCH OF THE E CARIBBEAN. HOWEVER...ACROSS THE FAR E CARIBBEAN...UPPER LEVEL DIFFLUENCE AND MOISTURE ARE APPROACHING FROM THE SW ATLC. THESE FACTORS ARE RESULTING IN SCATTERED SHOWERS FROM 16N-21N BETWEEN 61W-66W...WHICH ARE AFFECTING THE LEEWARD ISLANDS. ATLANTIC OCEAN... STRONG WEST-SOUTHWESTERLY FLOW ALOFT COVERS THE W ATLC. ALSO...A COLD FRONT EXTENDS FROM N OF HAITI NEAR 21N72W TO 27N69W TO 32N68W AND EXTENDS N OF THE DISCUSSION AREA. AT THE SAME TIME...DEEP LAYER MOISTURE FROM THE CARIBBEAN IS CIRCULATING ANTICYCLONICALLY ACROSS THE SW ATLC AROUND THE UPPER HIGH IN THE CENTRAL CARIBBEAN NEAR 15N73W. THE COMBINATION OF LOW LEVEL CONVERGENCE IN THE VICINITY OF THE COLD FRONT AND DEEP LAYER MOISTURE IS RESULTING IN ISOLATED MODERATE CONVECTION FROM 16N-29N BETWEEN 61W-66W...AFFECTING THE LEEWARD ISLANDS. FARTHER TO THE E...AN UPPER LEVEL TROUGH IS PRESENT WITH AN AXIS THAT EXTENDS FROM 8N55W TO 21N49W TO AN UPPER LOW NEAR 32N44W AND EXTENDS NE OF THE DISCUSSION AREA. THIS UPPER TROUGH IS ACCOMPANIED BY TWO SURFACE TROUGHS. ONE SURFACE TROUGH EXTENDS FROM 13N49W TO 18N49W TO 23N46W...WITH SCATTERED MODERATE CONVECTION FROM 14N-21N BETWEEN 40W-49W. THE SECOND SURFACE TROUGH EXTENDS FROM 25N45W TO 27N42W TO A 1014 MB SURFACE LOW AT 31N41W. TO THE NE OF THIS SURFACE LOW...A STATIONARY FRONT EXTENDS FROM 31N41W TO 32N39W TO NE OF THE DISCUSSION AREA...WITH SCATTERED MODERATE CONVECTION N OF 30N BETWEEN 34W-46W. FARTHER TO THE E...A SURFACE RIDGE EXTENDS FROM A 1028 MB SURFACE HIGH NEAR 36N18W TO 23N28W TO 15N30W...WITH SUBSIDENCE IN THE VICINITY OF THE SURFACE RIDGE BRINGING FAIR WEATHER CONDITIONS TO MUCH OF THE E ATLC. OVER THE TROPICAL ATLC...AN UPPER RIDGE IS PRESENT WITH AN AXIS THAT EXTENDS FROM 15N16W TO 11N24W TO 9N30W...WITH ASSOCIATED UPPER LEVEL DIVERGENCE ENHANCING THE CONVECTION IN THE VICINITY OF THE ITCZ AXIS. $$ COHEN