000 AXPZ20 KNHC 230233 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC THU APR 23 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 0230 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE ITCZ AXIS EXTENDS FROM 08N93W TO 03N103W TO 07N115W THEN RESUMES FROM 07N124W TO 04N140W. SCATTERED MODERATE CONVECTION IS WITHIN 120 NM N OF THE AXIS BETWEEN 125W AND 137W. ...DISCUSSION... GALE FORCE NORTHERLY WINDS ARE BLOWING OFF OF THE NORTHERN CALIFORNIA REDWOOD COAST WHICH ARE GENERATING NORTHERLY SWELL WITH SEAS OF 9-11 FT PROPAGATING SOUTHWARD INTO THE N CENTRAL DISCUSSION WATERS. THESE SEAS WILL PERSIST THROUGH EARLY FRI...THEN WILL GRADUALLY SUBSIDE FRI AFTERNOON AND NIGHT AS THE GALE FORCE WIND EVENT N OF THE AREA ENDS. A SURFACE TROUGH EXTENDS FROM 13N111W TO 09N118W TO 04N123W. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS WITHIN 150 NM EITHER SIDE OF THE TROUGH AXIS. OTHERWISE ONLY LIGHT TO MODERATE WINDS ARE OCCURRING EITHER SIDE OF THE TROUGH AXIS. HIGH PRESSURE AT 1033 MB IS LOCATED NW-N OF THE DISCUSSION WATERS NEAR 36N142W WITH A RIDGE AXIS EXTENDING SE THROUGH 32N138W TO 21N121W. THE PRESSURE GRADIENT SW OF THE RIDGING AND N OF THE ITCZ WHERE LOWER PRESSURES ARE PRESENT IS TIGHT ENOUGH TO SUPPORT FRESH TO STRONG TRADES FROM 10N TO 19N W OF 131W AS INDICATED BY RECENT ASCAT AND ASCAT-B SCATTEROMETER PASSES. THE ASSOCIATED NE WIND WAVES ARE COMMINGLING WITH LONG PERIOD NORTHERLY AND CROSS-EQUATORIAL SOUTHERLY SWELL WITH COMBINED SEAS OF 9-11 FT ACROSS THE W CENTRAL WATERS. EXPECT THESE CONDITIONS TO PERSIST THROUGH THE NEXT 48 HOURS WITH LITTLE CHANGE IN THE INTENSITY AND COVERAGE. E OF 110W...LIGHT TO MODERATE WINDS GENERALLY PREVAIL...WITH SEAS OF 4 TO 7 FT IN MIXED SWELL. THE EXCEPTION TO THIS IS ACROSS THE GULFS OF PANAMA AND PAPAGAYO...WHERE NOCTURNAL DRAINAGE FLOW WAS PRODUCING FRESH N AND NE WINDS RESPECTIVELY. GAP WINDS ACROSS THE GULF OF PAPAGAYO ARE EXPECTED TO PULSE TO 20-25 KNOTS EACH NIGHT BEGINNING TONIGHT INTO THE EARLY MORNING HOURS EACH DAY. THE GULF OF CALIFORNIA...A SURFACE TROUGH EXTENDS FROM SOUTHERN CALIFORNIA S-SE INTO THE N HALF OF THE GULF. THIS TROUGH HAS WEAKENED DURING THE PAST FEW HOURS BUT WILL BECOME MORE PRONOUNCED TONIGHT ALLOWING FOR S-SW WINDS N OF 29N E OF THE TROUGH TO INCREASE TO FRESH TO STRONG LEVELS. SEAS WILL BUILD BRIEFLY BETWEEN 5 AND 8 FT JUST TO THE EAST OF THE TROUGH DURING THE TIMES OF STRONGEST WINDS. $$ LEWITSKY