000 AXPZ20 KNHC 200956 RRA TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC THU MAR 20 2014 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL ANALYSIS. BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0930 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... ITCZ EXTENDS FROM 06N87W TO 05N100W TO 06N111W TO 04N120W TO 07N122W TO 05N140W. NO SIGNIFICANT CONVECTION. ...DISCUSSION... RELATIVELY QUIET CONDITIONS REMAIN ACROSS THE DISCUSSION AREA FOR THE TIME BEING. A WEAKENING CUT-OFF UPPER LOW IS IDENTIFIED NEAR 04N112W WITH A TROUGH EXTENDING NNW TO 17N115W. BROAD SCALE UPPER RIDGING COVERS THE AREA TO THE E OF THE LOW AND TROUGH WITH THE ASSOCIATED ANTICYCLONE OVER NORTHERN PANAMA. MOSTLY ZONAL FLOW ALOFT COVERS THE AREA W OF ABOUT 120W. AN UPPER TROUGH W OF THE AREA NEAR 144W IS GRADUALLY APPROACHING THE FAR WESTERN PORTION. THE SW TO W FLOW PATTERN AHEAD OF THIS TROUGH IS TRANSPORTING BROKEN TO OVERCAST MOSTLY MID AND UPPER CLOUDS ENE INTO THE AREA N OF 14N W OF 120W...AND TO THE N OF 18N E OF 120W TO OVER BAJA CALIFORNIA AND TO ACROSS NORTHERN MEXICO. WIDELY SCATTERED SHOWERS ARE POSSIBLE FROM 21N TO 27N BETWEEN 118W-121W. SATELLITE WATER VAPOR IMAGERY SHOWS MODERATE SUBSIDENCE ALOFT WITH ASSOCIATED DRY CONDITIONS KEEPING THE ATMOSPHERIC ENVIRONMENT RATHER STABLE OUTSIDE THE DESCRIBED AREA OF CLOUDINESS AND POSSIBLE WIDELY SCATTERED SHOWERS. AT THE SURFACE...A RIDGE EXTENDS INTO THE AREA THROUGH 32N131W TO NEAR 21N114W. HIGH PRES COVERS THE AREA N OF 17N W OF 112W. THE PRES GRADIENT BETWEEN THE RIDGE AND THE ITCZ REGION IS SUPPORTING A NE-E TRADES OF 15-20 KT FROM 07N TO 20N W OF 125W WITH SEAS OF 7-8 FT CONSISTING OF COMBINED WIND WAVES AND NW SWELLS. GLOBAL MODEL GUIDANCE SUGGESTS THAT THE RIDGE WILL CONTINUE TO BE THE DOMINANT FEATURE THROUGH THE NEXT 48 HOURS WITH LITTLE OVERALL CHANGE IN TRADES AND SEAS. A MODEST NW SWELL EVENT WITH SEAS OF 8 FT IS PRESENTLY CONFINED TO NW OF A LINE FROM 32N124W TO 24N140W. BY 24 HRS...THESE SWELLS WILL BE CONFINED TO N OF 25N BETWEEN 119W AND 123W...AND TO N OF 28N BETWEEN 118W AND 126W BY 48 HRS. GAP WINDS... THE NEXT GULF OF TEHUANTEPEC GAP WIND EVENT IS FORECAST TO BEGIN AT OR VERY NEAR DAYBREAK THIS MORNING AS THE PRES GRADIENT OVER SOUTHEASTERN MEXICO TIGHTENS AS A RESULT OF HIGH PRES THAT BUILDS SE ACROSS THE GULF OF MEXICO. THIS EVENT IS FORECAST TO START WITH N-NE WINDS OF 20-25 KT WITHIN 90 NM OF THE COAST ...THEN WITHIN 45 NM OF A LINE FROM 16N95W TO 14N95.5W BY THIS AFTERNOON. BY LATE TONIGHT...THESE WINDS INCREASE TO 20-30 KT WITH SEAS BUILDING TO 10 FT. THIS EVENT WILL BE SHORT-LIVED AS THE PRES GRADIENT WILL SLACKEN QUICKLY BY FRI AFTERNOON ALLOWING FOR THESE WINDS TO LESS THAN 20 KT...AND SEAS DECREASE TO 4-6 FT...EXCEPT FOR A SMALL BATCH OF 6-8 FT SEAS IN NE SWELLS DOWNWIND FROM THE GULF FROM 10N-14N BETWEEN 94W-97W. GULF OF PAPAGAYO...AN ASCAT PASS FROM 0342 UTC LAST NIGHT REVEALED THAT NE WINDS OF 20 KT HAVE ALREADY BEGUN TO FILTER THROUGH THE GULF...AND OUT TO THE PACIFIC NEAR 88W. THE SHIP WITH CALL SIGN "A8PQ8" AT 11N88W REPORTED SLIGHTLY HIGHER E WINDS NEAR 06 UTC. THIS PRESENT PULSE EVENT WILL BRIEFLY DIMINISH TO 20 KT OR LESS LATER DURING THE AFTERNOON. HIGH PRES OVER THE SE GULF OF MEXICO AND NW CARIBBEAN WILL INTERACT WITH LOW PRES OVER NW COLOMBIA LATE TONIGHT RESULTING IN A TIGHTENING OF THE PRES GRADIENT IN THE SW CARIBBEAN SEA. THE RESULT WILL BE SEEN AS NE 20-25 KT WINDS FUNNELING THROUGH THE GULF WITH WIND DRIVEN SEAS BUILDING TO 8-9 FT DOWNWIND OF THE GULF. THESE WINDS WILL SPREAD WESTWARD TO NEAR 90W DURING FRI MORNING BEFORE DIMINISHING TO 10-15 KT BY LATE FRI AFTERNOON OR EVENING AT WHICH TIME SEAS THEN LOWER TO AROUND 5-7 FT. YET ANOTHER ROUND OF NE-E 20-25 KT TRADES WILL FUNNEL THROUGH THE GULF LATE FRI NIGHT WITH SEAS BUILDING TO 8 FT. $$ AGUIRRE