000 AXPZ20 KNHC 180236 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC MON MAY 18 2015 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0045 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... LIGHT WINDS DOMINATE THE CLIMATOLOGICAL REGION OF THE ITCZ/MONSOON TROUGH IN THE NORTH EASTERN PACIFIC. THE ITCZ AXIS WAS ANALYZED FROM 05N130W TO 05N136W TO 08N139W TO A TROUGH FROM 10N140W TO 12N139W. SCATTERED MODERATE CONVECTION WAS WITHIN 180 NM E OF THE TROUGH AXIS FROM 10N TO 12N. A SPATTERING OF AREAS OF CONVECTION WERE NOTED TO THE E. SCATTERED MODERATE CONVECTION WAS N OF 06.5N TO THE COAST OF PANAMA AND COSTA RICA BETWEEN 79W- 84.5W...FROM 05N-08N BETWEEN 111W-114W AND FROM 09N-11N BETWEEN 131W-134W. ISOLATED MODERATE CONVECTION WAS WITHIN 180 NM EITHER SIDE OF A LINE FROM 08N86W TO 03N110W. ...DISCUSSION... 1019 MB HIGH PRESSURE NEAR 28N125W EXTENDS RIDGE AXES SOUTHEASTWARD TO 15N107W AND WESTWARD TO 24N140W. THE PRESSURE GRADIENT BETWEEN THE WESTERN RIDGE AND LOWER PRESSURE TO THE SOUTH ASSOCIATED WITH THE ITCZ AND A SURFACE TROUGH ANALYZED FROM 17N121W TO 08N126W IS GENERATING MODERATE TO FRESH TRADES MAINLY BETWEEN 10N-20N W OF 120W. THE FRESH TRADES ARE HELPING TO MAINTAIN AREAS OF SEAS AS HIGH AS 9 FT FROM 10N-16N W OF 135W AS WELL AS W OF THE TROUGH FROM 12N-16N BETWEEN 124W-130W IN MIXED NE...SW AND NW SWELL. THE TROUGH WILL MOVE W AROUND 5 KT...CARRYING THE AREA OF SEAS OVER 8 FT W WITH IT. A COLD FRONT WAS ANALYZED N OF THE WESTERN RIDGE AXIS FROM 1017 MB LOW PRESSURE N OF THE AREA NEAR 36N131W THROUGH 32N129W TO 29N133W TO 27N140W. THIS COLD FRONT WILL WEAKEN BY SUNRISE MON AS IT REACHES FROM 30N127W TO 28N130W TO 26N135W THEN DISSIPATE THROUGH MON AS IT SINKS SLOWLY SE. WINDS OVER FORECAST WATERS ARE NOT EXPECTED TO EXCEED A MODERATE BREEZE NEAR THE FRONT AND SEAS TO 8 FT SHOULD REMAIN CONFINED N OF 31N BEHIND THE FRONT. WEAK HIGH PRESSURE WILL REMAIN OVER THE NORTHERN WATERS WHICH WILL KEEP THE PRESSURE GRADIENT RELATIVELY CONSTANT AND MAINTAIN THE AREA OF MODERATE TO FRESH TRADES FROM 10N-20N W OF 120W...WITH OCCASIONAL AREAS OF FRESH TO STRONG WINDS POSSIBLY OCCURRING OFF THE N-NW EDGE OF THE AFOREMENTIONED SURFACE TROUGH. THE PRESSURE GRADIENT BETWEEN THE EASTERN RIDGE AND LOW PRESSURE ACROSS BAJA CALIFORNIA AND NW MEXICO IS PRODUCING A MODERATE NORTHWESTERLY BREEZE ALONG MOST OF THE PACIFIC COASTAL WATERS OF THE BAJA CALIFORNIA PENINSULA. THE GRADIENT WILL TIGHTEN SLIGHTLY BY MON AFTERNOON AS AN UPPER TROUGH SWINGS THROUGH THE BAJA CALIFORNIA PENINSULA AND INCREASES SURFACE TROUGHING. THIS SHOULD ALLOW WINDS TO BRIEFLY REACH A FRESH TO STRONG BREEZE OFFSHORE S OF PUNTA EUGENIA TO 25N MON EVENING WITH SEAS BUILDING TO 8 FT. SEAS WILL SUBSIDE BELOW 8 FT IN MIXED SW AND NW SWELL THROUGH SUNRISE TUE. THE TIGHTEST PRESSURE GRADIENT WILL SHIFT N ALONG THE COAST BY TUE EVENING...WITH FRESH TO STRONG N-NW WINDS AND SEAS TO 8 FT EXPECTED N OF 28N E OF THE COAST OF BAJA CALIFORNIA NORTE. GAP WINDS... GULF OF PAPAGAYO...WINDS WILL CONTINUE TO PULSE OVER THE GULF OF PAPAGAYO THE NEXT COUPLE OF DAYS. WINDS WILL PEAK NEAR 25 KT DURING THE LATE NIGHT AND EARLY MORNING HOURS WITH THE ADDED COMPONENT OF NOCTURNAL DRAINAGE FLOW. WINDS WILL DIMINISH TO 20 KT OR LESS DURING THE AFTERNOON AND EARLY EVENING HOURS. LOOKING AHEAD...ANOTHER STRONG SOUTHERN HEMISPHERIC SW SWELL WILL MOVE INTO THE REGIONAL WATERS LATE IN THE WEEK. SEAS WILL BUILD TO 8 FT AND GREATER ALONG THE EQUATORIAL WATERS BY THU MORNING. THIS PULSE OF LONG PERIOD SWELL IS EXPECTED TO REACH THE COASTLINES OF CENTRAL AMERICA BY LATE FRI. $$ SCHAUER