000 AXPZ20 KNHC 291533 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC FRI MAR 29 2013 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 1800 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH AXIS EXTENDS FROM 09N83W TO 06N90W. THE ITCZ AXIS EXTENDS FROM 06N90W TO 04N110W TO 03N125W TO 01N140W. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS WITHIN 45 NM EITHER SIDE OF THE ITCZ BETWEEN 92W AND 94W...FROM 04N TO 06N BETWEEN 118W AND 122W...AND ALSO FROM 01N TO 04N BETWEEN 121W AND 132W. ...DISCUSSION... A DEEP LAYERED CYCLONE JUST N OF AREA NEAR 32N134W HAS AN ATTENDANT TROUGH EXTENDING THROUGH 30N132W TO 20N140W. OTHERWISE MAINLY WESTERLY FLOW ALOFT COVERS THE REMAINDER OF THE DISCUSSION WATERS W OF 90W. MID TO UPPER LEVEL MOISTURE IS BEING ADVECTED BY A 85 TO 105 KT JET FROM THE DEEP TROPICS S OF HAWAII TO THE NE ACROSS THE BAJA CALIFORNIA PENINSULA AND NW MEXICO AHEAD OF THE TROUGH AND UNDER A BROAD UPPER RIDGE. ANOTHER UPPER TROUGH EXTENDS FROM NEAR 20N110W THROUGH 10N110W TO BEYOND 00N115W. VERY DRY AIR IS EVIDENT ON SATELLITE IMAGERY S OF 18N BETWEEN 105W AND 120W...EXCEPT W OF THE TROUGH JUST N OF THE EQUATOR WHERE UPPER LEVEL DIFFLUENCE IS HELPING TO SUPPORT THE CONVECTION MENTIONED ABOVE ALONG THE ITCZ. 1018 MB SURFACE HIGH PRES NEAR 29N118W WILL WEAKEN SLIGHTLY WHILE STILL MANAGING TO HOLD ITS GROUND AGAINST AN APPROACHING COLD FRONT WHICH EXTENDS FROM 30N134W TO 27N135W TO 25N140W. THIS FRONT IS BEING SUPPORTED BY THE DEEP LAYERED CYCLONE AND TROUGH MENTIONED ABOVE. FRESH TO STRONG WINDS ARE OCCURRING W OF THE FRONT WITH SIMILAR SW WINDS N OF 27N JUST AHEAD OF THE FRONT. LARGE NW SWELLS UP TO 14 FT ARE ATTEMPTING TO PROPAGATE S OF 30N...HIGHEST REMAINING ALONG AND N OF 30N. THE FRONT WILL WEAKEN WHILE SLOWLY TRYING TO MOVE E...EVENTUALLY DISSIPATING BY SUN MORNING WITH ANY REMAINING WINDS AND SEAS DIMINISHING AND SUBSIDING BY THEN. LOOKING AHEAD...A SECOND COLD FRONT IS FORECAST TO APPROACH THE NW CORNER LATE SUN NIGHT WITH FRESH TO STRONG SOUTHERLY WINDS AHEAD OF IT. MOST OF THE ENERGY ASSOCIATED WITH THIS FRONT SHOULD REMAIN W AND N OF THE AREA...WITH NW SWELL STILL MANAGING TO IMPACT THE NW CORNER EARLY NEXT WEEK. GULF OF TEHUANTEPEC...THE PRES GRADIENT OVER SE MEXICO HAS WEAKENED CONSIDERABLY...ALTHOUGH N TO NE 20 TO 30 KT WINDS ARE STILL LIKELY EARLY THIS MORNING WITH ENHANCED DRAINAGE FLOW. WINDS WILL DIMINISH TO 20 TO 25 KT LATER TONIGHT THROUGH EARLY SAT...THEN TO 20 KT OR LESS BY SAT AFTERNOON. THEREAFTER EXPECT LIGHT AND VARIABLE WINDS WITH 2 TO 4 FT SEAS SUN THROUGH AT LEAST THE MIDDLE OF NEXT WEEK. GULF OF PAPAGAYO...A TIGHT PRES GRADIENT REMAINS ALONG THE INTERIOR SPINE OF CENTRAL AMERICA SUPPORTING NE TO E 20 TO 30 KT WINDS IN AND DOWNWIND OF THE GULF OF PAPAGAYO ALL THE WAY TO 08.5N92W...ALONG WITH SEAS OF 8 TO 11 FT. WINDS WILL DIMINISH SLIGHTLY TO 20 TO 25 KT...STRONGEST DURING SAT MORNING AND SUN MORNING DURING DOWNSLOPE DRAINAGE ON THE W SIDE OF THE MOUNTAIN RANGE...WITH THE COVERAGE OF THESE WINDS ALSO SHRINKING THROUGH TIME. GULF OF PANAMA...MODERATE TO FRESH NORTHERLY WINDS WILL CONTINUE TO BLOW THROUGH THE GULF OF PANAMA TODAY...DIMINISHING TONIGHT. SEAS WILL BUILD TO 6 TO 7 FT JUST DOWNWIND OF THE STRONGEST WINDS. NE SWELLS GENERATED IN THE GULFS OF TEHUANTEPEC AND PAPAGAYO IS COMMINGLING WITH LONGER PERIOD NW SWELL ACROSS THE WATERS FROM FROM 03N TO 10N BETWEEN 93W AND 112W...WITH SEAS IN THE 8 TO 10 FT RANGE. THESE SEAS WILL GRADUALLY SUBSIDE TO 8 TO 9 FT THIS WEEKEND WHILE THEY CONTINUE TO PROPAGATE TO THE W. $$ LEWITSKY