000 AXNT20 KNHC 082333 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT TUE MAY 08 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 10N15W 4N27W 1N40W 1N50W. SCATTERED MODERATE CONVECTION IS WITHIN 60 NM N AND 180 NM S OF THE AXIS BETWEEN 23W-41W. ISOLATED MODERATE IS WITHIN 60 NM EITHER SIDE E OF 23W. ...SPECIAL FEATURE... A LARGE NON-TROPICAL LOW PRESSURE SYSTEM...CENTERED NEAR 31N78W...OR ABOUT 150 NM EAST-SOUTHEAST OF THE GEORGIA AND SOUTH CAROLINA COASTS...HAS BEEN MOVING SLOWLY WESTWARD AT 5 TO 10 MPH MUCH OF THE DAY...ALTHOUGH HAS JOGGED A BIT TO THE N OVER THE PAST COUPLE HOURS. THIS SYSTEM IS PRODUCING GALE FORCE CONDITIONS WITH SHIP AND BUOY OBSERVATIONS SHOWING MAX WINDS IN THE 35-45 KT RANGE. THESE WINDS ARE PRODUCING HIGH SEAS AND HEAVY SURF ALONG THE COASTS OF NORTH CAROLINA...SOUTH CAROLINA...GEORGIA AND FLORIDA. ASSOCIATED SHOWER ACTIVITY HAS CHANGED LITTLE THROUGHOUT THE DAY AND SIGNIFICANT STRENGTHENING OF THIS SYSTEM IS NOT EXPECTED. THE LOW IS BEING MONITORED FOR SIGNS OF TROPICAL OR SUBTROPICAL CYCLONE DEVELOPMENT...AND AN AIR FORCE RESERVE RECONNAISSANCE AIRCRAFT WILL BE AVAILABLE TO INVESTIGATE THE SYSTEM TOMORROW MORNING...IF NECESSARY. PLEASE REFER TO THE HIGH SEAS FORECAST AND STATEMENTS FROM LOCAL WEATHER SERVICE OFFICES FOR MORE DETAILS. ...DISCUSSION... GULF OF MEXICO... THE SPECIAL FEATURE DISCUSSED ABOVE IS PRODUCING ABUNDANT SUBSIDENCE AND ADVECTING PLEASANTLY DRIER AND COOLER AIR ACROSS THE CENTRAL AND ERN GULF. VISIBLE IMAGERY SHOWS AREAS OF SMOKE...ORIGINATING FROM FIRES IN FLORIDA AND S GEORGIA... STEERED BY THE LOW-LEVEL FLOW SWD IN THE E GULF FROM 24N-27N E OF 88W. THE SMOKE APPEARS THICKEST NEAR THE SW COAST OF FLORIDA WHERE VISIBILITIES HAVE BEEN REDUCED BELOW 1 SM AT TIMES. FARTHER W...STRONG W TO NWLY FLOW ON THE NRN PERIPHERY OF TROPICAL EPAC RIDGE IS TRANSPORTING A MID TO HIGH LEVEL CLOUD DECK INTO THE WRN GULF. AT THE SFC...A MODERATE HIGH PRES RIDGE IN THE SRN U.S. IS PRODUCING 10-15 KT NE TO E FLOW ACROSS THE ERN AND MIDDLE GULF VEERING TO THE SE IN THE W GULF. CARIBBEAN SEA... WEAK PRES PATTERN IN THE WRN CARIB CONTINUES TO PRODUCE LIGHT NE WINDS GENERALLY IN THE 5-15 KT RANGE. THE TRADES INCREASE TO 20 KT IN THE E CARIB AS RIDGING FROM THE AZORES HIGH AS BUILT CLOSER TIGHTENING THE GRADIENT. IN THE UPPER LEVELS...A TROUGH/RIDGE PATTERN REMAINS IN PLACE. STRONG SWLY UPPER FLOW BETWEEN THESE FEATURES IS TRANSPORTING A SWATH OF DEBRIS MID TO HIGH LEVEL CLOUDS AND EMBEDDED SHOWERS FROM CONVECTIVE BLOW-UPS ALONG THE ITCZ...WHICH RUNS ACROSS PANAMA AND COLOMBIA...TO THE GREATER ANTILLES. DOPPLER RADAR FROM SAN JUAN PUERTO RICO IS SHOWING SOME SCATTERED SHOWERS MOVING NE TOWARD THE ISLAND. THIS ACTIVITY IS LIKELY MORE ASSOCIATED WITH LOW-LEVEL MOISTURE PICKED UP BY THE TRADES. WESTERN ATLANTIC... THE LARGE LOW PRES SYSTEM CONTINUES TO BE THE HIGHLIGHT. THE ASSOCIATED FRONTAL BOUNDARIES ARE SLOWLY DISSIPATING WITH THE TRAILING BOUNDARY EXTENDING FROM A TRIPLE POINT NEAR 33N71W ACROSS THE CENTRAL BAHAMAS TO NRN CUBA. A STATIONARY FRONT RUNS FROM THE TRIPLE POINT ALONG 31N/32N TO 54N WHERE IT CONNECTS TO A WEAK COLD FRONT FURTHER NE. SCATTERED SHOWERS ARE WITHIN 180 NM OF THE LOW. MORE CONVECTIVE WEATHER IS FIRING UP WELL TO THE E OF THE LOW IN A DIFFLUENT ZONE N OF 25N BETWEEN 71W-73W. FOR MORE DETAILS REFER TO THE SPECIAL FEATURE SECTION ABOVE. CENTRAL AND EASTERN ATLANTIC... A 1029 MB HIGH CENTERED BETWEEN THE AZORES AND PORTUGAL IS IN CONTROL OF THE PATTERN PROVIDING WIDESPREAD FAIR WEATHER AND MODERATE TRADES ACROSS THIS PORTION OF THE ATLC. SAHARAN DUST APPEARS TO HAVE SPREAD TO ABOUT 40W...ALTHOUGH THICKEST E OF 30W. THIS DUST IS ERODING THE TYPICAL STRATOCUMULUS DECK ASSOCIATED WITH THE SUBTROPICAL RIDGE. THERE IS ONLY A SMALL AREA OF DEEP CLOUD COVER CONTAINED N OF 30N BETWEEN 40W-46W ASSOCIATED WITH A WEAK AREA OF LOW PRES AND FRONTAL BOUNDARY JUST N OF THE AREA. AN UPPER LOW NW OF THE CANARY ISLANDS NEAR 33N19W IS BEGINNING TO OPEN. ITS ASSOCIATED TROUGHING IS ALSO FLATTENING ALTHOUGH STILL EVIDENT FROM THE LOW TO THE CAPE VERDE ISLANDS. THIS UPPER FEATURE IS ONLY GENERATING SCATTERED PATCHES OF CIRRUS. $$ CANGIALOSI