000 AXNT20 KNHC 271106 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 705 AM EST MON MAR 27 2006 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...WEATHER OBSERVATIONS... RADAR...AND METEOROLOGICAL ANALYSIS. BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1100 UTC. ...ITCZ... THE ITCZ AXIS IS CENTERED ALONG 6N10W 3N20W 2N30W EQ46W 2S45W. SCATTERED MODERATE CONVECTION IS LOCATED WITHIN 100 NM MAINLY SOUTH OF THE AXIS BETWEEN 13W-23W. ELSEWHERE...SCATTERED SHOWERS AND ISOLATED TSTMS ARE WITHIN 150 NM ON EITHER SIDE OF THE AXIS. ...DISCUSSION... GULF OF MEXICO... A DEEP LAYER TROUGH IS PULLING EASTWARD OVER THE W ATLANTIC AS A MID-UPPER LEVEL RIDGE IS IN PLACE OVER N MEXICO AND THE CENTRAL U.S. OVER THE GULF OF MEXICO...WESTERLY UPPER LEVEL WINDS PREVAIL. MODERATE TO STRONG SUBSIDENCE LIES ACROSS THE AREA WITH THE DRIEST/MOST STABLE AIR OVER THE SE GULF. AT THE SURFACE...A 1028 MB HIGH IS CENTERED OVER THE OHIO VALLEY WITH RIDGING EXTENDING SWARD INTO THE GULF OF MEXICO ADVECTING UNSEASONABLY COOL AND DRY AIR OVER THE EASTERN GULF AND FLORIDA. SFC WINDS TURN FROM NORTHERLY E OF 86W TO EASTERLY AND THEN SELY W OF 93W. THE E/SE WINDS ARE POOLING MOISTURE IN THE W GULF AND CAUSING UPSLOPE CONDITIONS OVER THE SIERRA MADRE MOUNTAINS. THICK LOW CLOUDS...SCATTERED SHOWERS AND FOG ARE BANKED UP AGAINST THE TOPOGRAPHY AND SPREAD 125 NM OFFSHORE INTO THE GULF. THIS MOISTURE IS SPREADING NWARD INTO TEXAS CARRIED BY THE SE RETURN FLOW. ONE MORE RELATIVELY COOL AND DRY DAY WILL OCCUR TODAY ACROSS THE EASTERN GULF BEFORE THE SFC HIGH PRESSURE SYSTEM MOVES OFF THE U.S. EAST COAST THIS EVENING ALLOWING SE RETURN FLOW TO ALSO DEVELOP ACROSS THE EASTERN PART OF THE BASIN WARMING TEMPERATURES TO NEAR NORMAL VALUES. CARIBBEAN... A STRONG MID/UPPER LEVEL HIGH IS CENTERED NEAR 12N58W WITH ITS ANTICYCLONIC FLOW ENCOMPASSING MUCH OF THE CARIBBEAN. A SUB-TROPICAL JET IS RIDING AROUND THE N PERIPHERY OF THE STRONG UPPER HIGH DRAWING A FAIR AMOUNT OF MID-UPPER LEVEL MOISTURE FROM S AMERICA AND THE EPAC AND SPREADING IT OUT ACROSS THE CARIBBEAN AND CENTRAL ATLANTIC. THIS MOISTURE IS DRYING OUT AS IT TRAVELS EASTWARD. AT THE SURFACE...THE TAIL END OF A W ATLANTIC FRONTAL BOUNDARY IS STATIONARY AND LIES OVER HISPANIOLA. OCCASIONAL SCATTERED SHOWERS ARE OCCURRING OVER HISPANIOLA AND PARTS OF THE NW CARIBBEAN SEA NEAR THE BOUNDARY. NLY UPSLOPE FLOW HAS PRODUCED MAINLY OVERCAST LOW-LEVEL CLOUDINESS AND ISOLATED SHOWERS FROM NRN NICARAGUA TO GUATEMALA AND BELIZE. THE FRONTAL BOUNDARY IS EXPECTED TO BECOME STRETCHED HORIZONTAL FROM PUERTO RICO/VIRGIN ISLANDS TO HISPANIOLA THIS AFTERNOON AND REMAIN STATIONARY FOR MUCH OF THE UPCOMING WEEK...INCREASING THE CHANCE OF RAIN OVER THESE ISLANDS. ATLANTIC... A STRONG LOW PRESSURE SYSTEM PRODUCING HURRICANE FORCE WINDS IS LOCATED OFF THE COAST OF NOVA SCOTIA WITH ITS ASSOCIATED DEEP-LAYER TROUGH COVERING THE ATLANTIC W OF 65W N OF 28N. A POLAR JET FLOWS AROUND THE SW SIDE OF THE LOW FROM THE MID-ATLANTIC STATES AND CONVERGES WITH THE SUBTROPICAL JET RIDING ALONG THE N PERIPHERY OF THE UPPER HIGH IN THE CARIBBEAN...PRODUCING STRONG UPPER LEVEL FLOW AND AN AREA OF STRONG SUBSIDENCE FROM THE SE GULF TO THE BAHAMAS. AT THE SURFACE...A COLD FRONT ENTERS THE AREA ALONG 32N44W 25N56W AND THE BECOMES STATIONARY ACROSS HISPANIOLA. MULTILAYER CLOUDS AND SCATTERED SHOWERS ARE LOCATED WITHIN 150 NM OF THE FRONT N OF 27N WITH MOISTURE MORE DIFFUSE S OF THERE. A POST-FRONTAL TROUGH IS ENHANCING THE COLD AND DRY AIR BEHIND THE FRONT AND ENTERS THE AREA ALONG 32N51W 27N67W. COLD AIR STRATOCUMULUS CLOUDS ARE WIDESPREAD BEHIND THE SFC TROUGH. A LINE OF CLOUDS AND SCATTERED SHOWERS EXTEND FROM THE WINDWARD PASSAGE ACROSS THE SE BAHAMAS ASSOCIATED WITH A WEAK SFC TROUGH. FARTHER EAST...MID-UPPER LEVEL RIDGING COVERS THE AREA FROM 30W-50W. SURFACE HIGH PRESSURE DOMINATES THE CENTRAL ATLANTIC WITH A 1024 MB HIGH CENTERED NEAR 28N36W GENERATING FAIR WEATHER ACROSS A GOOD PART OF THE CENTRAL AND EASTERN ATLANTIC N OF THE ITCZ. A DEEP LAYER TROUGH LIES E OF 30W N OF 25N. A SOUTHWESTERLY UPPER LEVEL JET EXTENDS FROM 27N24W TO 32N16W NEWARD TO PORTUGAL ENHANCING SCATTERED SHOWERS N OF 22N TO THE RIGHT OF THE JET AXIS. A COASTAL SURFACE TROUGH IS ALONG THE NE COAST OF AFRICA ALONG 32N8W 26N14W. IN THE TROPICAL ATLANTIC...A STRONG UPPER LEVEL ANTICYCLONE COVERS THE AREA PRODUCING STRONG SUBSIDENCE FROM 55W EWARD BETWEEN 8N-20N LIMITING ANY SHOWER ACTIVITY. $$ CANGIALOSI