000 AXNT20 KNHC 051101 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT FRI JUN 05 2009 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1045 UTC. ...TROPICAL WAVES... A WEAK TROPICAL WAVE IS ALONG 34W/35W S OF 9N MOVING W 10-15 KT. THIS WAVE IS ASSOCIATED WITH A LOW AMPLITUDE MAXIMUM IN DEEP LAYER MOISTURE BASED ON THE TOTAL PRECIPITABLE WATER PRODUCT FROM CIMSS. THE CIMSS WAVETRAK PRODUCT DEPICTS LOW LEVEL CYCLONIC CIRCULATION NEAR THE WAVE. THIS WAVE IS INTERACTING WITH DRY LOW/MID-LEVEL SAHARAN AIR...WHICH IS INHIBITING DEEP CONVECTION IN THE VICINITY OF THIS WAVE. HOWEVER...SCATTERED SHOWERS ARE OCCURRING FROM 2N-5N BETWEEN 31W-35W. A TROPICAL WAVE EXTENDS FROM 18N47W TO 8N50W TO 1N49W MOVING W NEAR 15 KT. THIS WAVE IS ASSOCIATED WITH A RATHER HIGHLY AMPLIFIED MAXIMUM IN DEEP LAYER MOISTURE BASED ON THE TOTAL PRECIPITABLE WATER PRODUCT FROM CIMSS. SATELLITE IMAGERY INDICATES THAT THE WAVE IS ASSOCIATED WITH A LARGE INVERTED-V SIGNATURE IN THE LOW LEVEL CLOUD FIELD...WITH SATELLITE DERIVED WINDS INDICATING CYCLONIC CURVATURE IN THE LOW LEVEL FLOW NEAR THIS WAVE. THIS WAVE APPEARS TO BE INTERACTING WITH DRY LOW/MID-LEVEL SAHARAN AIR...WHICH IS SUPPRESSING DEEP CONVECTION ACROSS MOST AREAS NEAR THIS WAVE. HOWEVER...SCATTERED MODERATE CONVECTION IS FROM 5N-8N BETWEEN 43W-49W. A TROPICAL WAVE IS OVER THE GULF OF HONDURAS AND CENTRAL AMERICA ALONG 86W/87W S OF 17N MOVING W AROUND 10 KT. THE TOTAL PRECIPITABLE WATER PRODUCT FROM CIMSS INDICATES THAT THIS WAVE COINCIDES WITH A MAXIMUM IN DEEP LAYER MOISTURE. THE CIMSS WAVETRAK PRODUCT ALSO DEPICTS LOW LEVEL CYCLONIC CIRCULATION NEAR THE WAVE. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS OVER THE SW CARIBBEAN FROM 10N-12N BETWEEN 79W-84W. ADDITIONAL CONVECTION IS OCCURRING NEAR THIS TROPICAL WAVE IN THE EAST PACIFIC REGION. ...THE ITCZ... THE ITCZ AXIS IS CENTERED ALONG 10N14W 5N22W 2N33W 1N44W AND INTO NE BRAZIL ALONG THE EQUATOR NEAR 52W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 3N-8N BETWEEN 12W-26W. SCATTERED MODERATE CONVECTION IS FROM 3N-6N BETWEEN 27W-30W. ...DISCUSSION... GULF OF MEXICO... AN UPPER LEVEL TROUGH IS PRESENT ACROSS THE GULF REGION WITH AN AXIS EXTENDING FROM 22N87W TO 27N88W TO 30N88W TO N OF THE DISCUSSION AREA. ATMOSPHERIC INSTABILITY NEAR THE UPPER LEVEL TROUGH...AND UPPER LEVEL DIFFLUENCE IN MOIST SOUTHWESTERLY FLOW ALOFT E OF THE UPPER LEVEL TROUGH AXIS...ARE SUPPORTING SCATTERED SHOWERS AND THUNDERSTORMS ACROSS THE GULF N OF 23N E OF 86W INCLUDING ADJACENT INLAND AREAS ALONG THE GULF COAST. THIS ACTIVITY IS BEING SUPPORTED BY LOW LEVEL CONVERGENCE NEAR A SURFACE TROUGH EXTENDING FROM 25N85W TO THE FLORIDA BIG BEND NEAR 30N83W. ALSO...THE AFOREMENTIONED UPPER LEVEL TROUGH IS ASSOCIATED WITH A SURFACE COLD FRONT OVER THE GULF THAT EXTENDS FROM 24N95W TO 27N90W TO A 1007 MB LOW OVER THE W FLORIDA PANHANDLE NEAR 30N87W. LOW LEVEL CONVERGENCE AND ATMOSPHERIC INSTABILITY ARE SUPPORTING SCATTERED SHOWERS AND THUNDERSTORMS ALONG AND WITHIN 90 NM E OF THE COLD FRONT. THE 1007 MB SURFACE LOW IS FORECAST TO DISSIPATE DURING THE NEXT DAY. ACROSS MUCH OF THE W GULF...DEEP LAYER DRY AIR IN NORTHWESTERLY FLOW ALOFT IS SUPPORTING GENERALLY FAIR WEATHER. THE COLD FRONT IS FORECAST TO EXTEND FROM THE FLORIDA BIG BEND TO THE CENTRAL GULF TONIGHT AND THEN SLOWLY DISSIPATE THROUGH LATE SATURDAY....WITH SW TO W WINDS OF 10 TO 15 KT AHEAD OF THE COLD FRONT ACROSS PORTIONS OF THE MIDDLE AND E GULF. CARIBBEAN SEA... DEEP LAYER DRY AIR IN NORTHWESTERLY FLOW ALOFT IS RESULTING IN GENERALLY FAIR WEATHER ACROSS MUCH OF THE CARIBBEAN. HOWEVER... UPPER LEVEL MOISTURE AND HIGH LEVEL CLOUDS CONTINUE TO STREAM EAST-NORTHEASTWARD ACROSS THE NW CARIBBEAN. A SURFACE RIDGE N OF THE CARIBBEAN IN THE CENTRAL AND E ATLC COMBINED WITH BROAD LOW PRESSURE OVER COLOMBIA WILL CONTINUE TO PRODUCE NE TO E TRADE WINDS OF 20 TO 25 KT ACROSS MUCH OF THE SOUTHERN CARIBBEAN. THE TRADE WINDS ARE ADVECTING POCKETS OF LOW LEVEL MOISTURE AND ISOLATED SHOWERS WESTWARD ACROSS THE CARIBBEAN...WITH THE GREATEST CONCENTRATION OF THESE SHOWERS FROM 18N-21N BETWEEN 79W-86W. THE TRADES ARE FORECAST TO RELAX SATURDAY NIGHT THROUGH MONDAY AS THE SURFACE RIDGE IN THE CENTRAL AND E ATLC WEAKENS. ATLANTIC OCEAN... UPPER LEVEL DIFFLUENCE IN MOIST SOUTHWESTERLY FLOW ALOFT OVER THE SW NORTH ATLC IS RESULTING IN SCATTERED SHOWERS AND THUNDERSTORMS N OF 23N W OF 75W INCLUDING THE NW BAHAMAS AND ADJACENT INLAND AREAS OF FLORIDA. ADDITIONALLY...SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE OCCURRING N OF 24N BETWEEN 53W-62W...WHERE ATMOSPHERIC INSTABILITY IS PRESENT NEAR AN UPPER LEVEL TROUGH. ACROSS MUCH OF THE CENTRAL AND E ATLC...A BROAD SURFACE RIDGE IS RESULTING IN GENERALLY FAIR WEATHER. THE SURFACE RIDGE IS ASSOCIATED WITH A 1026 MB SURFACE HIGH NEAR 34N42W. THIS SURFACE HIGH IS FORECAST TO MOVE SOUTHWESTWARD DURING THE NEXT DAY AND BE LOCATED NEAR 31N54W AS A 1026 MB SURFACE HIGH AT 06/0600 UTC. ACROSS THE E ATLC...A SURFACE TROUGH EXTENDS FROM 27N26W TO 30N21W TO 32N18W TO NE OF THE DISCUSSION AREA. LOW LEVEL CONVERGENCE IS SUPPORTING SCATTERED SHOWERS WITHIN 60 NM EITHER SIDE OF THIS SURFACE TROUGH. ACROSS THE TROPICAL ATLC...AN UPPER LEVEL RIDGE IS S OF 13N E OF 52W WITH AN UPPER LEVEL HIGH NEAR 8N22W. UPPER LEVEL DIVERGENCE NEAR THE UPPER LEVEL HIGH AND UPPER LEVEL RIDGE IS ENHANCING THE CONVECTION ASSOCIATED WITH THE ITCZ. $$ COHEN