000 AXPZ20 KNHC 042203 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 2205 UTC THU FEB 04 2010 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2100 UTC. ...ITCZ... INTERTROPICAL CONVERGENCE ZONE AXIS ANALYZED ALONG 05N77W TO 07N90W TO 07N105W TO 03N136W TO 05N140W. SCATTERED MODERATE CONVECTION CAN BE FOUND WITHIN 75 NM N AND 50 NM S OF THE ITCZ AXIS BETWEEN 135W AND 137W. ...DISCUSSION... A DEEP LAYER TROUGH THAT EXTENDS S FROM THE TEXAS PANHANDLE SW TOWARD MANZANILLO AND INTO THE TROPICAL PACIFIC DOMINATES THE WEATHER PATTERN OVER MUCH OF THE REGION W OF 110W. ALOFT...A POWERFUL ZONAL JET ALONG 30N LIES OVER N WATERS W OF 125W. WINDS TURN NORTHWESTERLY AS IT APPROACHES THE TROUGH AXIS AND WEAKEN TO 80-100 KT AS THEY ROUND THE BASE OF THE TROUGH AND TURNS INTO A 120-140 KT SOUTHERLY JET INTO THE U.S. SOUTHERN PLAINS. UPPER LEVEL DIFFLUENCE BETWEEN THIS TROUGH AND AN UPPER RIDGE AXIS OVER FLORIDA IS SUPPORTING WIDESPREAD CLOUDINESS AND PRECIPITATION PRIMARILY E OF THE TROUGH AXIS OVER NE MEXICO AND THE REMAINDER OF MEXICO S OF 20N. OVER THE TROPICAL PACIFIC WATERS...A BROAD SURFACE TROUGH REFLECTION OF THE TROUGHING ALOFT LIES WITHIN 90 NM EITHER SIDE OF A LINE FROM 17N103W TO 07N113W. 20 KT WINDS CAN BE FOUND ON THE NE SIDE OF THE TROUGH WHICH IS EXPECTED TO SHIFT EASTWARD AND DISSIPATE FRI. LOW LEVEL MOISTURE CONTINUES TO BE CONVERGED ON THE EASTERN EDGE OF THIS SURFACE TROUGHING BUT THE DEEP CONVECTION PREVIOUSLY FOUND IN THIS AREA HAS DIMINISHED AS THE REAR RIGHT QUADRANT OF THE SOUTHERLY UPPER JET PULLS EASTWARD AWAY FROM THIS LOW LEVEL MOISTURE POOL. HOWEVER...40-60 KT MID-LEVEL SW WINDS CONTINUE TO PUMP MOSITURE NORTHEASTWARD INTO MEXICO...WITH A BAND OF MID TO HIGH CLOUDS FOUND WITHIN 270 NM OF A LINE FROM THE ITCZ NEAR 110W TO 18N98W. MODERATE TO STRONG SUBSIDENCE DOMINATES THE REGION JUST EAST OF HERE AND INTO CENTRAL AMERICA FROM HONDURAS SOUTHWARD. 1017 MB HIGH PRES NEAR 26N119W HAS BEEN SQUEEZED EWD BY A STRONG COLD FRONT OVER NW WATERS. TRADE WINDS HAVE DECREASED BELOW 20 KT AS A RESULT OF THE WEAK HIGH PRES DISPLACED WELL AWAY FROM THE ITCZ. THE AFOREMENTIONED COLD FRONT WILL CONTINUE TO PASS EASTWARD INTO SOUTHERN CALIFORNIA BY FRI EVENING AND DISSIPATING OVER NE WATERS SAT EVENING. THE GALE WARNING PREVIOUSLY IN EFFECT FOR THE SOUTHERLY FLOW IN ADVANCE OF THIS FRONT WAS BROUGHT DOWN AT 1800 UTC. THE 1834 UTC ASCAT PASS SUGGESTS THAT WINDS ARE RAPIDLY DECREASING BELOW 30 KT AS THE CORE OF THE SYSTEM LIFTS NORTHEASTWARD. ANOTHER COLD FRONTAL SYSTEM CURRENTLY NORTH OF HAWAII WILL APPROACH THIS WEAKENING SYSTEM TOMORROW...SUSTAINING THE 20 KT WINDS OVER NW WATERS BEFORE THEY DIMINISH SAT. THIS NEW SYSTEM WILL BRING ANOTHER SURGE OF NW SWELL INTO THE REGION...WITH SEAS EXPECTED TO REACH 22 FT IN FAR NW WATERS FRI AFTERNOON. AS THE COLD FRONT DISSIPATES OVER NE WATERS SAT...HIGH PRES IS EXPECTED TO BUILD TO THE W...ALLOWING 20 KT NE TRADE WINDS TO RETURN TO W WATERS. GAP WINDS... ASCAT DATA FROM 1516 UTC CONTINUE TO SHOW 20 TO 25 KT WINDS THROUGH THE GULF OF PAPAGAYO. THESE GAP WINDS ARE EXPECTED TO DIMINISH BELOW 20 KT BY FRI AFTERNOON. SIMILARLY...THE 20 TO 25 KT WINDS SEEN IN THAT ASCAT PASS IN THE GULF OF PANAMA ARE EXPECTED TO DIMINISH SAT MORNING WHEN THE PRES GRADIENT BETWEEN LOW PRES IN COLOMBIA AND HIGH PRES TO THE NORTH WEAKENS AS A COLD FRONT ENTERS THE FAR NW CARIBBEAN. THE NEXT TEHUANTEPEC EVENT WILL BEGIN EARLY SAT BEHIND THIS FRONT...BUT IT DOES NOT APPEAR THAT IT WILL BECOME STRONG ENOUGH TO REQUIRE A WARNING. ELSEWHERE...FORECAST WATERS ARE DOMINATED BY NW SWELL AND GENERALLY LIGHT WINDS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ SCHAUER