000 AXNT20 KNHC 310554 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 105 AM EST THU JAN 31 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0515 UTC ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 2N2W 2N10W 4N30TO EQUATOR AT 50W. SCATTERED MODERATE CONVECTION NOTED IN SMALL 60 NM DIAMETER CLUSTERS AT 4.5N305W 3.5N33W AND 2.5N42W. CONVECTION IS MOST IMPRESSIVE ALONG THE AXIS WELL INLAND S AMERICA AT 1S53W. ...DISCUSSION... GULF OF MEXICO... IN THE UPPER LEVELS A NEW SHORTWAVE TROUGH IS DIGGING SE ACROSS CENTRAL TEXAS WHILE A SHORTWAVE RIDGE...ORIGINATING FROM AN ANTICYCLONE CENTER NEAR JAMAICA...GENTLY RIDGES ACROSS THE AREA ALONG POINTS 21N97W 30N85W. A BAND OF UPPER MOISTURE IS STREAMING ENE AND EVAPORATING OVER THE NORTHERN GULF WATERS. DRY UPPER AIR IS INDICATED S OF LINE FROM W CENTRAL FLORIDA TO OLD MEXICO AT 22N97W. AT THE SURFACE A FRONT HAS STALLED ACROSS N CENTRAL FLORIDA TO NEAR 26N88W WHERE THE FRONTAL REMNANTS ARE NOW MOVING BACK N AS A WARM FRONT TO 25N96W. BROKEN TO LOCALLY OVERCAST LOW CLOUDS WITH EMBEDDED SHOWERS ARE NOTED N OF THIS FRONTAL TROUGH. THE NEW COLD FRONT WILL MOVE INTO THE NW GULF WATERS TODAY. CARIBBEAN SEA... IN THE UPPER LEVELS AN ANTICYCLONE IS CENTERED NEAR JAMAICA WITH THE ASSOCIATED RIDGE DOMINATING THE CARIBBEAN AND IS ACCOMPANIED BY VERY DRY UPPER AIR THAT IS SUPPRESSING DEEP CONVECTIVE DEVELOPMENT. THE SOUTHERN EXTENSION OF AN ATLC UPPER TROUGH IS STILL EVIDENT OVER THE NE CARIBBEAN ISLANDS. THE REMNANTS OF THE ASSOCIATED SURFACE FRONT ARE DISSIPATING ALONG 14N60W 13N70W ACCOMPANIED BY BROKEN LOW CLOUDS AND WARM TOP SHOWERS. THE LOW LEVEL FLOW IS NE OVER THE AREA N OF THIS FRONT ADVECTING LOCALLY BROKEN LOW CLOUDS AND EMBEDDED LIGHT SHOWERS OVER THE NE PORTION. ANOTHER AREA OF BROKEN TO OVERCAST LOW CLOUDS IS NOTED WITHIN 150 NM 16N80W AND IS MOVING W IN THE BRISK EASTERLY TRADES THAT DOMINATE THE W CARIBBEAN. ATLC OCEAN... AN UPPER TROUGH IS LIFTING OUT NE OF THE DISCUSSION AREA OVER THE NORTHERN W ATLC. A SURFACE COLD FRONT STILL EXTENDS SW ACROSS THE NW WATERS FROM 32N76W TO THE FLORIDA COAST AT 29N81W ACCOMPANIED BY BROKEN LOW CLOUDS AND LIGHT SHOWERS. AN UPPER LEVEL SHORTWAVE RIDGE EXTENDS N FROM THE CARIBBEAN OVER THE W ATLC CRESTING ALONG POINTS 30N80W 31N67W 24N64W. A BAND OF UPPER MOISTURE LIES ALONG THE NORTHERN PERIPHERY OF THIS RIDGE... ROUGHLY WITHIN 90 NM EITHER SIDE OF LINE 29N80W 30N71W 26N94W. A DEEP LAYERED CYCLONE IS NEAR 24N56W AND IS SHIFTING S WITH TIME WITH AN UPPER TROUGH EXTENDING S ALONG 20N53W 15N51W. UPPER DIFFLUENCE IS ENHANCING CONVECTION OVER THE NE SEMICIRCLE OF THE CYCLONE ALONG THE SURFACE COLD FRONT LYING ALONG 24N52W 14N60W. THE ASSOCIATED SURFACE LOW PRES IS AT 27.5N57W 1012 MB. SURFACE HIGH PRES IS CENTERED NEAR 28N70W 1023 MB RIDGING SW TO THE STRAITS OF FLORIDA. DRY UPPER AIR IS INDICATED S OF 25N W OF 65W AND S OF 23N BETWEEN 65W AND 53W. THE E ATLC IS DOMINATED BY AN UPPER CYCLONE CENTERED AT 28N27W WITH A TROUGH EXTENDING S TO 10N20W. UPPER DIFFLUENCE IS ENHANCING CONVECTION E OF THE CYCLONE NEAR 26N25W. AN UPPER RIDGE EXTENDS N ACROSS THE EQUATOR CRESTING ALONG 15N47W 22N36W THEN THE UPPER FLOW TURNS CYCLONIC INTO THE TROUGH ALREADY MENTIONED. THIN CIRRIFORM CLOUDS ARE NOTED WITHIN THE RIDGE BECOMING MORE DENSE S OF 6N BETWEEN 35W AND 50W. AT THE LOW LEVELS BRISK NE FLOW AND LOCALLY BROKEN STRATOCUMULUS CLOUDS ARE NOTED E OF 50W. $$ NELSON