000 AXNT20 KNHC 162335 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT SUN MAR 16 2008 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 4N8W 3N24W 1N34W CROSSING THE EQUATOR NEAR 37W TO NE BRAZIL NEAR 3N43W. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS WITHIN 180 NM N OF THE AXIS BETWEEN 21W-25W...37W-40W AND N OF 4N E OF 12W. ...DISCUSSION... GULF OF MEXICO... MAINLY ZONAL MID-UPPER LEVEL FLOW AND WIDESPREAD SUBSIDENCE LIES OVER THE GULF OF MEXICO THIS EVENING. THIS PATTERN IS PROVIDING LITTLE SUPPORT FOR A NEARLY STATIONARY FRONTAL BOUNDARY EXTENDING FROM SW FLORIDA TO S TEXAS ALONG 26N82W 27N90W 29N96W. THE ONLY RELATED MOISTURE IS A THIN ROPE CLOUD ALONG THE BOUNDARY...OTHERWISE SKIES ARE FAIR TO MOSTLY CLEAR ACROSS THE REGION. SFC WINDS ARE STRONGEST...E TO SE AT 20-30 KT OR SO IN THE NW GULF. THESE STIFF WINDS WILL SHIFT MORE TOWARDS THE S... EXPAND EWD AND INCREASE TO GALE FORCE IN ABOUT 36 HOURS AS THE PRES GRADIENT TIGHTENS BETWEEN APPROACHING LOW PRES OVER THE S AND SW STATES AND STRONG CANADIAN HIGH PRES OVER THE GREAT LAKES AND NORTHEAST. AN ASSOCIATED STRONG COLD FRONT IS EXPECTED TO ENTER THE W GULF ON TUE WITH STRONG NLY WINDS BUILDING BEHIND IT. CARIBBEAN SEA... A WELL DEFINED MID-UPPER HIGH REMAINS CENTERED OVER THE S CENTRAL CARIB NEAR 13N71W. WIDESPREAD DRY STABLE AIR IS ASSOCIATED WITH THIS RIDGE...ESPECIALLY ON ITS E SIDE. THIS STABLE AIR IS CAPPING THE TYPICAL LOW-LEVEL CLOUD PATCHES STEERED BY MODERATE TRADES...WHICH AGAIN APPEAR MORE SUPPRESSED THAN USUAL EXCEPT FOR AN AREA OVER AND IN THE VICINITY OF PUERTO RICO AND IN THE NW CARIB FROM 17N-20N BETWEEN 83W-86W. ATLANTIC OCEAN... A 988 MB LOW PRES SYSTEM LOCATED WELL OFF THE EASTERN CONUS NEAR 37N65W IS RAPIDLY INTENSIFYING AS IT TRACKS NE. ITS TRAILING COLD FRONT ENTERS THE REGION NEAR 32N70W AND EXTENDS SWWD TO S FLORIDA. GALE CONDITIONS HAVE LIKELY BEGUN N OF 28N W OF THE FRONT AND WITHIN 240 NM E OF THE FRONT N OF 28N. ONLY THIN NARROW BANDS OF LOW CLOUDS MARK THE FRONT GREATLY SUPPRESSED BY A VERY SUBSIDENT ENVIRONMENT W OF 60W. A SERIES OF MID TO UPPER SHORTWAVES ARE OVER THE SUBTROPICAL CENTRAL AND EASTERN ATLC. THE MOST VIGOROUS IS A SMALL CUT OFF LOW SPINNING NEAR 28N32W. THIS MID TO UPPER SYSTEM COUPLED WITH THE TAIL END OF A WEAKENING STALLED FRONT FROM 32N27W TO 27N35W IS PRODUCING SCATTERED SHOWERS AND TSTMS N OF 28N BETWEEN 30W-33W. SIMILAR ACTIVITY IS OCCURRING WITH A SHORTWAVE TO THE W FROM 26N-32N BETWEEN 43W-48W. MUCH OF THE TROPICAL ATLC IS IN A SLIGHT INDUCED TROUGHING REGIME ALOFT N OF 10N AND MODEST RIDGING S OF 10N. THIS IS LEADING TO QUIET CONDITIONS EXCEPT FOR PATCHES OF INDUCED CONVECTION IN THE ITCZ. IN THE LOWER LEVELS...A WEAK WWD MOVING TROUGH ALONG 55W/56W FROM 12N-18N IS PRODUCING A FEW SHOWERS WITHIN 120 NM OF ITS AXIS...OTHERWISE TRANQUIL CONDITIONS PREVAIL ASSOCIATED WITH WEAK SFC RIDGING. $$ CANGIALOSI