000 AXPZ20 KNHC 101548 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC TUE MAY 10 2016 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1500 UTC. ...MONSOON TROUGH/INTERTROPICAL CONVERGENCE ZONE... THE EPAC MONSOON TROUGH EXTENDS W FROM THE PACIFIC COAST OF COSTA RICA AT 09.5N84W TO 10N96W TO LOW PRES 1009 MB NEAR 12N108.5W TO 06N120W...THEN TRANSITIONS TO ITCZ...CONTINUING ON TO 07N129W TO BEYOND 05.5N140W. WIDELY SCATTERED MODERATE TO STRONG CONVECTION IS NOTED FROM 01.5N TO 08.5N E OF 88W TO COAST OF COLOMBIA. ELSEWHERE WIDELY SCATTERED MODERATE TO STRONG CONVECTION IS NOTED WITHIN 150 NM EITHER SIDE OF TROUGH BETWEEN 92W AND 118W. SCATTERED STRONG CONVECTION IS NOTED WITHIN 90 NM OF ITCZ W OF 134W. SCATTERED MODERATE TO STRONG CONVECTION IS OBSERVED WITHIN 360 NM ACROSS THE SW QUADRANT OF THE LOW NEAR 12N108.5W. ...DISCUSSION... N OF 15N E OF 120W... A SURFACE TROUGH WILL PERSIST ALONG THE LENGTH OF THE BAJA CALIFORNIA PENINSULA THIS WEEK...BECOMING MOST PRONOUNCED DURING AFTERNOON AND EARLY EVENING DURING PEAK HEATING. A NW TO SE SURFACE RIDGE WILL MEANDER ACROSS THE TROPICAL WATERS FROM NEAR 23N120W TO BEYOND 15N103W THROUGH THE UPCOMING WEEKEND. THIS SCENARIO IS EXPECTED TO MODERATE NW WINDS ALONG THE PACIFIC NEAR AND OFFSHORE WATERS OF THE BAJA PENINSULA...WITH WINDS EXPECTED TO INCREASE TO AROUND 20 KT DURING LATE AFTERNOON HOURS ACROSS TYPICALLY SEA BREEZE PRONE AREAS OF THE WEST COAST. SEAS WERE RUNNING 4 TO 5 FT THIS MORNING IN MIXED NW AND SW SWELL...AND ARE NOT EXPECTED TO CHANGE SIGNIFICANTLY DURING THE NEXT FEW DAYS. THE PRESSURE GRADIENT ACROSS THE REGION IS EXPECTED TO TIGHTEN ON SAT WITH MODERATE TO FRESH NW FLOW DEVELOPING ACROSS THE EPAC WATERS FROM 27-32N E OF 120W. LIGHT TO GENTLE ANTICYCLONIC FLOW IS EXPECTED AROUND THE QUASI- STATIONARY RIDGE ELSEWHERE ACROSS THE OPEN EPAC WATERS W OF 97W THIS WEEK...EXCEPT MODERATE N TO NE WIND FLOW IS EXPECTED S OF 17N BETWEEN 105 AND 120W IN RESPONSE TO A WEAK LOW PRESSURE SYSTEM CURRENTLY NEAR 12N108.5W SHIFTING GRADUALLY WESTWARD ALONG THE MONSOON TROUGH. LIGHT ONSHORE FLOW IS EXPECTED ACROSS THE GULF OF TEHUANTEPEC THROUGH FRI EVENING...WITH MODEL GUIDANCE SUGGESTING THAT STRONG NORTHERLY DRAINAGE FLOW WILL DEVELOP LATE FRI NIGHT...AND MAY REACH 25-30 KT...AND PERSIST THROUGH SUNRISE ON SAT BEFORE DIMINISHING. COMBINED SEAS OF 4-6 FT ARE CURRENTLY OBSERVED ACROSS THE OPEN PAC WATERS W OF 100W IN MIXING LONG-PERIOD CROSS EQUATORIAL S SWELL AND LONG PERIOD NW SWELL. S OF 15N E OF 110W... MODERATE NE TO E NOCTURNAL DRAINAGE FLOW WAS OBSERVED ACROSS AND JUST N OF THE PAPAGAYO REGION OVERNIGHT WITH SEAS AROUND 5 FT.GLOBAL MODELS INDICATE OFFSHORE WINDS WILL DIMINISH DURING THE AFTERNOON HOURS AND BECOME SOUTHEASTERLY...THEN RETURN TO OFFSHORE OVERNIGHT. THIS PATTERN WILL REPEAT ITSELF OVER THE NEXT FEW DAYS. TO THE SW...A TROPICAL LOW IS SEEN IN SATELLITE IMAGERY NEAR 12N108.5W AND IS ESTIMATED AT 1009 MB. THE LOW IS FORECAST TO MEANDER FOR A DAY OR SO ACCOMPANIED BY MODERATE CYCLONIC WINDS BEFORE SHIFTING W AND PASSING W OF 110W EARLY THU. OTHERWISE...GENTLE E TO NE FLOW IS EXPECTED N OF THE MONSOON TROUGH...AND MODERATE S TO SW FLOW IS EXPECTED S OF THE TROUGH AXIS. ELSEWHERE FROM THE EQUATOR TO 32N E OF 140W... A RIDGE EXTENDS SE FROM NEAR 32N132W TO BEYOND 23N120W. FRESH NE WINDS ARE NOTED ACROSS THE TROPICS BETWEEN THE RIDGE AND THE ITCZ ALL TO THE W OF 115W...WITH SEAS OF 7-8 FT CURRENTLY OBSERVED ACROSS THE TROPICAL WATERS FROM 06N TO 09.5N W OF 128.5W. THE PRES GRADIENT IMPOSED BY THE RIDGE IS EXPECTED TO MAINTAIN FRESH NE WINDS WITHIN 240 NM N OF THE ITCZ FOR THE NEXT FEW DAYS...AND KEEP SEAS 7-8 FT IN A MIX OF NE WIND WAVES AND MIXED SW AND NW SWELL. THE NEXT COLD FRONT WILL REACH NEAR 30N140W ON WED ACCOMPANIED BY A MODERATE TO FRESH S-SW-NW WIND SHIFT. A SURFACE HIGH WILL SHIFT S ALONG 130W REACHING NEAR 28N ON THU AND BLOCK THE EASTWARD PROGRESSION OF THE COLD FRONT...WHICH IS EXPECTED TO STALL FROM ABOUT 32N131W TO 26N140W BY FRI. $$ STRIPLING