000 AXNT20 KNHC 230522 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 105 AM EST FRI FEB 23 2007 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHEASTERN 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0515 UTC. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 8N12W 4N21W 2S34W 4S40W. ISOLATED SHOWERS/TSTMS WITHIN 75 NM OF THE AXIS BETWEEN 15W-28W. SCATTERED MODERATE CONVECTION S OF 2N W OF 34W SPREADING ACROSS PORTIONS OF FAR NE BRAZIL...FRENCH GUIANA...AND SURINAME. ...DISCUSSION... GULF OF MEXICO... FAIR WEATHER EXISTS UNDER STRONG SFC HIGH PRES ANCHORED WELL N IN CENTRAL CANADA. A 1022 MB HIGH EMBEDDED IN THE RIDGE HAS BEEN NEARLY STATIONARY OVER THE PAST 24 HOURS NEAR 29N91W. A WEAK COLD FRONT CUTS THRU THE RIDGE EXTENDING FROM NEAR JAX ACROSS THE NE GULF WATERS TO SRN MS. THE FRONT IS DIFFICULT TO TRACK ON SATELLITE IMAGERY AS THERE IS LITTLE OR NO CLOUDS/MOISTURE ASSOCIATED WITH IT. SLIGHTLY LOWER PRESSURES AND A SLIGHT WIND SHIFT DEFINE THE BOUNDARY. ELSEWHERE A WEAK SURFACE TROUGH OVER THE ERN BAY OF CAMPECHE IS CAUSING AN E/W ORIENTED BAND OF LOW/MID-LEVEL CLOUDS FROM 23N-26N BETWEEN 89W-95W. IN THE MID AND UPPER LEVELS...RIDGING IS ALSO THE THEME EXTENDING N FROM CENTRAL AMERICA WITH A SUBTROPICAL JET BRANCH RIDING ALONG THE NRN PERIPHERY ADVECTING A CONSIDERABLE AMOUNT OF UPPER MOISTURE ACROSS NRN MEXICO AND INTO THE N GULF...CURRENTLY CONFINED N OF 27N W OF 90W. THE TAIL END OF UPPER TROUGHING LIES OFF THE U.S. EAST COAST PROVIDING THE UPPER SUPPORT FOR THE AFOREMENTIONED COLD FRONT. OTHERWISE THE AREA IS UNDER A SUBSIDENT ENVIRONMENT WITH LITTLE CLOUD COVER. THE WEAK COLD FRONT IS EXPECTED TO BECOME NEARLY STATIONARY AND INCREASINGLY DIFFUSE FROM SOUTH FLORIDA TO NEW ORLEANS FRI AFTERNOON. A SECOND STRONGER COLD FRONT WILL MOVE OFF THE TEXAS COAST SAT AFTERNOON PRECEDED BY SCATTERED SHOWERS/TSTMS N OF 27N ALONG THE GULF COAST...BUT IT TOO WILL STALL OVER THE NRN GULF WATERS LATE SUN. CARIBBEAN... HIGH PRES ACROSS THE GULF OF MEXICO AND W ATLC IS PRODUCING MODERATE TO FRESH TRADES...EXCEPT STRONGER OFF THE COAST OF COLOMBIA. THE LARGE-SCALE ENVIRONMENT IS DOMINATED BY A STRETCHED E/W MID-LEVEL RIDGE ALIGNED ALONG 15N PROVIDING AN ABUNDANCE OF MODERATE/STRONG SUBSIDENCE ACROSS THE ENTIRE AREA. THE MOST STABLE CONDITIONS LIE FROM WRN COLOMBIA TO EL SALVADOR WHERE WV ENHANCEMENTS ARE SHOWING UP IN THE DRIEST RANGE. THIS IS DUE TO UPPER LEVEL CONFLUENCE BETWEEN THE RIDGE AND A 500 MB LOW CENTERED OVER VENEZUELA NEAR 7N66W. BENEATH THE STRONG MID LEVEL CAP...A FEW SMALL PATCHES OF LOW LEVEL MOISTURE ARE BEING STIRRED UP AND DRIVEN BY THE TRADES...PARTICULARLY ACROSS THE ISLANDS OF PUERTO RICO AND HISPANIOLA WHERE THERE IS LIKELY SOME LAND INFLUENCE AND POSSIBLY SOME ENHANCEMENT FROM A WEAK TROUGH IN THE ATLC. NO MAJOR PATTERN CHANGES APPEAR TO BE IN STORE FOR THE AREA OVER THE NEXT DAY OR TWO SO SIMILAR TRADES AND WEATHER CONDITIONS ARE ANTICIPATED. WEST ATLANTIC... GENTLE TROUGHING LIES ACROSS THE MAJORITY OF THE REGION ON THE S SIDE OF A LARGE POLAR VORTEX. TWO SHORTWAVE TROUGHS ARE EMBEDDED AND ROTATING IN THE BROAD CYCLONIC FLOW. ONE OF THESE JUST CLIPS THE AREA WITH ITS BASE NEAR 31N78W PROVIDING SUPPORT FOR THE WEAK COLD FRONT MENTIONED IN THE GULF SECTION. THE OTHER IS BETTER DEFINED STRETCHING FROM 32N54W TO NEAR 24N67W. BEHIND THIS QUICK MOVING AXIS...SUBSIDENCE IS ENHANCED AND WIDESPREAD PROVIDING STABLE CONDITIONS ALOFT. A RELATED ILL-DEFINED SFC TROUGH RUNS FROM 30N59W ACROSS THE CENTRAL BAHAMAS. ANOTHER SFC TROUGH...REMNANTS OF A RATHER LONG LIVED FRONTAL BOUNDARY...IS ALONG 26N52W 20N64W. NEITHER OF THESE BOUNDARIES ARE PRODUCING MUCH WEATHER AND MAINLY DEFINED BY WIND SHIFTS AS DEPICTED BY A QSCAT PASS NEAR 23Z. THE WEAK SFC BOUNDARIES ARE EXPECTED TO PUSH E WITH THE UPPER SUPPORT AS HIGH PRES BUILDS OVER THE WEN PORTION OF THE REGION ON SAT. EAST ATLANTIC... SFC HIGH PRES IS THE RULE ANCHORED BY A 1029 MB ABOUT 250-300 NM WNW OF THE CANARY ISLANDS. THIS HIGH IS PROVIDING MODERATE TO STRONG TRADES ACROSS A GOOD PORTION OF THE AREA. ALOFT...THE FLOW HAS FLATTENED AND IS NOW BASICALLY ZONAL ACROSS MOST OF THE SUBTROPICAL AREAS. IN THE TROPICS...THE PATTERN IS A LITTLE MORE COMPLEX WITH AN EXTENSIVE BROAD FLAT RIDGE STRETCHED ACROSS THE EQUATORIAL ATLC. A CUT OFF UPPER LOW NEAR THE CAPE VERDE ISLANDS IS ERODING THE N SIDE OF THE RIDGE ADVECTING SOME PATCHY HIGH CLOUDS FROM 14N-23N BETWEEN 23W-29W. OVER THE NEXT COUPLE OF DAYS...NWP MODELS LITTLE CHANGE AT THE SFC BUT AN AMPLIFICATION IN THE UPPER PATTERN AS A LARGE RIDGE DEVELOPS IN RESPONSE TO A DEEPENING TROUGH IN THE NW ATLC. $$ CANGIALOSI