000 AXNT20 KNHC 111741 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT MON JUN 11 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...TROPICAL WAVES... A LARGE TROPICAL WAVE IS ALONG 35W S OF 20N MOVING QUICKLY TO THE WNW NEAR 25 KT. WHILE THIS WAVE STILL HAS AN IMPRESSIVE SHIELD OF LOW CLOUDS...WHICH HAS MADE TRACKING IT EASY SINCE EMERGING OFF THE W COAST OF AFRICA 2 DAYS AGO...IT LACKS ANY DEEP SHOWER OR TSTM ACTIVITY. A TROPICAL WAVE HAS BEEN ADJUSTED SLIGHTLY ALONG 45W S OF 11N MOVING W 10-15 KT. THIS ADJUSTMENT IS BASED ON MID-LEVEL TURNING AND A WEAK INVERTED V-SHAPE SEEN ON SATELLITE IMAGES. A 24 HOUR LOOP OF THESE IMAGES INDICATES CLEAR WWD CONTINUITY OF THIS STRUCTURE SO THERE IS GOOD CONFIDENCE IN THE UPDATED PSN. EMBEDDED CLUSTERS OF SCATTERED SHOWERS AND TSTMS ARE WITHIN 150 NM EITHER SIDE OF THE WAVE AXIS. A TROPICAL WAVE IS IN THE CENTRAL CARIB ALONG 73W/74W S OF 17N MOVING W 10-15 KT. THERE IS A BROAD AREA OF LOW LEVEL TURNING IN THE VICINITY...BUT THIS IS LIKELY ASSOCIATED WITH CLIMATOLOGICAL FLOW AROUND THE OROGRAPHY. OTHERWISE...LITTLE STRUCTURE AND PRECIP IS ASSOCIATED WITH THIS FEATURE. A TROPICAL WAVE IS IN THE WESTERN CARIB ALONG 84W S OF 17N MOVING W 10-15 KT. THE INTERACTION BETWEEN THIS WAVE...OR SOME ASSOCIATED ENERGY THAT BROKE OFF...AND PRONOUNCED UPPER DIFFLUENCE E OF AN UPPER LOW NEAR THE WRN TIP OF CUBA IS FUELING SCATTERED MODERATE CONVECTION FROM 15N-20N BETWEEN 78W-83W. HOWEVER...IT NOW SEEMS MORE LIKELY THAT THE WAVE AXIS MAY BE FURTHER W...CLOSER TO 90W...BASED ON AN IMPROVED AREA OF LOW-LEVEL TURNING IN THE TROPICAL EPAC AND PATCHES OF CONVECTIVE FLARE-UPS IN THAT VICINITY. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 9N13W 6N20W 5N30W 4N44W 4N52W. BESIDES FOR THE ACTIVITY ASSOCIATED WITH THE TROPICAL WAVES...SCATTERED MODERATE/ISOLATED STRONG IS WITHIN 90 NM EITHER SIDE OF THE AXIS BETWEEN 18W-22W. ISOLATED MODERATE IS WITHIN 120 NM N OF THE AXIS BETWEEN 36W-43W. ...DISCUSSION... THE GULF OF MEXICO... MUCH OF THE GULF IS IN NWLY UPPER FLOW REGIME BETWEEN RIDGING CENTERED OVER NRN MEXICO NEAR 27N101W AND AN UPPER LOW NEAR THE WRN TIP OF CUBA. THIS DRY FLOW IS PROVIDING A STABLE AIRMASS ALLOWING SKIES TO BE FAIR TO MOSTLY CLEAR. THE SFC PRES PATTERN IS VERY WEAK WITH A 1013 MB FRONTAL LOW OVER THE FLA PANHANDLE AND A SFC TROUGH ANALYZED ALONG 89W/90W S OF 26N...ALLOWING WINDS TO BE LIGHT AND VARIABLE. THERE IS NOT MUCH DEFINING THE LOW AND ASSOCIATED FRONTAL BOUNDARIES BESIDES FOR A WEAK WIND SHIFT AND SLIGHTLY LOWER PRESSURES. THE TROUGH IS A LITTLE BETTER DEFINED WITH BROAD LOW-LEVEL TURNING...EVIDENT IN BUOY AND QSCAT DATA...AND EMBEDDED ISOLATED SHOWERS WITHIN 60 NM OF THE AXIS. THIS WEAK PATTERN IS EXPECTED TO PERSIST THRU MID-WEEK KEEPING WINDS AND SEAS OF LITTLE CONCERN. THE CARIBBEAN SEA... SCATTERED MODERATE CONVECTION IN THE NW CARIB FROM 15N-20N BETWEEN 78W-83W IS THE ACTIVE REGION IN THIS BASIN TODAY. THIS ACTIVITY IS ASSOCIATED WITH DIFFLUENCE ALOFT TO THE E OF A FAIRLY VIGOROUS UPPER LOW SPINNING ABOVE THE WRN TIP OF CUBA. AIDING IN THE SUPPORT IS SOME LOW-LEVEL LIFT FROM A TROPICAL WAVE...OR MORE LIKELY THE NRN BRANCH THAT BROKE OFF FROM THE MAIN SYSTEM. ELSEWHERE...A LARGE PATCH OF SCATTERED SHOWERS AND ISOLATED TSTMS LIE JUST TO THE E OF THE LESSER ANTILLES FROM 13N-20N BETWEEN 57W-61W. SIMILARLY...THIS MOISTURE IS ASSOCIATED WITH UPPER DIFFLUENCE BETWEEN AN UPPER RIDGE PARKED OVER THE CENTRAL CARIB NEAR 14N71W AND TROUGHING TO THE NE OF THE AREA. THE REMAINDER OF THE CARIB WATERS IS FREE OF DEEP MOISTURE...ALTHOUGH TYPICAL TRADE WIND SHOWERS COULD OCCUR JUST ABOUT ANYWHERE. THE ATLANTIC OCEAN... THE WRN PART OF THE DISCUSSION AREA LIES TO THE S OF A LARGE OCCLUDED LOW PRES SYSTEM. UPPER TROUGHING EXTENDS INTO THE AREA ALONG 65W N OF 24N. AN ASSOCIATED COLD FRONT IS ANALYZED TO THE E OF BERMUDA ALONG 32N64W 31N72W. LITTLE SIGNIFICANT MOISTURE LIES IN THIS REGION BESIDES FOR ONE SMALL CLUSTER OF MODERATE CONVECTION FROM 29N-32N BETWEEN 77W-79W. FARTHER E...WV IMAGERY SHOWS AN UPPER HIGH CENTERED NEAR 23N55W AND MUCH MORE EXTENSIVE RIDGING STRETCHING W FROM AFRICA ALONG 20N TO ABOUT 40W. UPPER TROUGHING...LIES BETWEEN THESE RIDGES EXTENDING FROM 32N35W TO AN UPPER LOW NEAR 23N47W CONTINUING TO 18N52W. AN ASSOCIATED WEAKENING COLD FRONT ENTERS THE AREA NEAR 32N24W AND EXTENDS W-SW ALONG 31N31W 32N36W. UPPER DIFFLUENCE IS PRODUCING PATCHES OF SCATTERED SHOWERS BETWEEN 55W-65W AND WITHIN 120 NM E OF THE UPPER LOW. BESIDES FOR THE TROPICAL WAVES AND THE WEAK COLD FRONTS CLIPPING THE NRN PORTION OF THE DISCUSSION AREA...HIGH PRES IS THE THEME ANCHORED BY A 1029 MB HIGH NEAR 34N41W. THIS HIGH IS AIDING IN THE MOSTLY FAIR WEATHER AND PRODUCING A LARGE AREA OF MODERATE TRADES ACROSS THE TROPICAL ATLC. $$ CANGIALOSI