000 AXNT20 KNHC 021742 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT MON JUL 02 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 TROPICAL WAVE HAS BEEN RELOCATED TO THE W ALONG 43W/44W S OF 19N MOVING W 15-20 KT. EARLIER TODAY...THIS WAVE WAS REPOSITIONED E ALONG 35W TO MATCH UP WITH THE FORMATION OF A BROAD LOW PRES SYSTEM. HOWEVER...AFTER ANALYZING A LONG-TERM SATELLITE LOOP...IT APPEARS MORE LIKELY THAT THIS WAVE LEFT BEHIND A PIECE OF ENERGY IN THE ITCZ WHICH HAS FORMED INTO THE LOW. THE LARGER SCALE WAVE IS STILL DISCERNIBLE ON VISIBLE SAT IMAGES AS A SURGE-LIKE STRUCTURE. IN ADDITION...THE GFS MOISTURE FIELDS AGREE WELL WITH SATELLITE IMAGES WHICH GAVE ME MORE CONFIDENCE IN THIS ADJUSTMENT. REGARDLESS...THE MORE INTERESTING FEATURE IS THE LOW PRES SYSTEM TO THE E OF THE WAVE ANALYZED 1014 MB NEAR 8N36W. WHILE THIS LOW DOES HAVE A FAIRLY WELL DEFINED LOW TO MID LEVEL CIRCULATION...CONVECTION IS LIMITED AND CONFINED WITHIN 180 NM S AND W OF THE CENTER. TROPICAL WAVE WAS ANALYZED ACROSS CENTRAL AMERICA ALONG 88W/89W S OF 21N MOVING W 15 KT. LITTLE WAVE STRUCTURE IS NOTED IN THIS VICINITY. THERE IS A POSSIBILITY THAT THIS WAVE COUPLE BE FURTHER W NEAR 94W TO MESH UP WITH A MID-LEVEL SWIRL WHICH HAS BECOME MORE EVIDENT OVER THE PAST COUPLE HOURS. HOWEVER...DUE TO THE UNCERTAINTY DECIDED TO HOLD CONTINUITY. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 9N13W 8N22W 9N33W 8N43W 7N58W. SCATTERED MODERATE CONVECTION IS LOCATED WITHIN 120 NM S OF THE AXIS E OF 25W. SCATTERED SHOWERS AND TSTMS ARE WITHIN 60 NM EITHER SIDE OF THE AXIS W OF 52W. ...DISCUSSION... GULF OF MEXICO... AN UPPER LOW IS SPINNING OFF THE TAMPA BAY COAST NEAR 28N83.5W. INSTABILITY ASSOCIATED WITH THIS FEATURE IS PRODUCING BROKEN CLOUDINESS AND ISOLATED SHOWERS ACROSS THE E GULF. THE COMBINATION OF THIS UPPER ENERGY AND A LOW-LEVEL BOUNDARY ACROSS THE FL STRAITS WILL LIKELY HELP FIRE UP SCATTERED SHOWERS AND TSTMS OVER THE FLA PENINSULA LATER THIS AFTERNOON. AN UPPER RIDGE IS BUILDING W OF THE LOW ALIGNED ALONG 93W. DIFFLUENCE ALOFT BETWEEN THIS RIDGE AND ANOTHER UPPER LOW OVER TEXAS IS PRODUCING NUMEROUS SHOWERS AND TSTMS ACROSS SE TEXAS AND THE EXTREME NW GULF. AT THE SFC...WEAK 1018 MB HIGH CENTER IS LOCATED NEAR 26N87W. THIS HIGH IS PRODUCING LIGHT AND SOMEWHAT VARIABLE WINDS ACROSS THE E GULF. HOWEVER...MODERATE SELY WINDS ARE EVIDENT IN THE SW PORTION WHERE THE PRES GRADIENT TIGHTENS DUE TO A NEARBY TROPICAL WAVE. CARIBBEAN SEA... AN UPPER HIGH CENTERED OVER THE YUCATAN PENINSULA EXTENDS A RIDGE WWD TOWARD JAMAICA. THE UPPER PATTERN THEN FOLDS INTO A TROUGH E OF THERE WITH THE AXIS EXTENDING FROM THE ATLC ACROSS THE DOMINICAN REPUBLIC TO THE S CARIB NEAR 13N76W. THIS PATTERN IS ALLOWING MODESTLY DRY NLY UPPER FLOW TO DOMINATE PROVIDING A FAIRLY STABLE AIRMASS OVER THE CARIB WATERS....EXCEPT ACROSS THE NW AND SE CORNERS WHERE THERE IS A BROKEN LAYER OF MID-HIGH LEVEL CLOUDINESS AND EMBEDDED ISOLATED SHOWERS AND TSTMS. SCATTERED PATCHES OF DEEP MOISTURE IS OVER PANAMA AND THE COASTAL WATERS ASSOCIATED WITH THE ITCZ. AT THE SFC...A 1036 Z QSCAT PASS SHOWED A LARGE AREA OF 20-30 KT ELY TRADES ACROSS THE CARIB...STRONGEST IN THE CENTRAL PORTION. THESE STRONG WINDS ARE CARRYING TYPICAL LOW CLOUD STREAMERS WITH EMBEDDED ISOLATED SHOWERS ACROSS THE REGION. LITTLE CHANGE IS EXPECTED TOMORROW. ATLANTIC OCEAN... A COLD FRONT HAS NOW MOVED S ALONG THE NRN BOUNDARY EXTENDING FROM NEAR BERMUDA TO THE GEORGIA COAST. A SFC TROUGH LIES TO THE S OF THIS BOUNDARY ANALYZED FROM 30N72W ACROSS THE FLORIDA KEYS. LOW-LEVEL CONVERGENCE NEAR THIS TROUGH ALONG WITH MOIST UPPER SWLY FLOW AND DIFFLUENCE...BETWEEN A VERY LARGE POLAR LOW AND AN UPPER HIGH NEAR 24N65W...IS PRODUCING SCATTERED SHOWERS AND TSTMS N OF 25N BETWEEN 66W-76W. LIGHTER ISOLATED SHOWERS AND TSTMS LIE W OF 77W. FARTHER E...RIDGING DOMINATES BOTH AT THE SFC AND ALOFT. THE SFC AZORES HIGH IS ANALYZED 1033 MB NEAR 35N30W. THIS HIGH IS PRODUCING A LARGE AREA OF MODERATE TRADES ACROSS THE ATLC. STRONG NLY WINDS ARE NEAR THE AFRICAN COAST DUE TO THE TIGHTENING PRES GRADIENT BETWEEN THE HIGH AND INVERTED TROUGHING OVER THE CONTINENT. THE UPPER RIDGE IS FURTHER S ALIGNED E-W ALONG 24N. WIDESPREAD DRY AIR ALOFT IS PROVIDING ABUNDANT FAIR WEATHER ACROSS THE CENTRAL AND E ATLC. $$ CANGIALOSI