000 AXPZ20 KNHC 211613 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC TUE APR 21 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1530 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE EASTERN PACIFIC MONSOONAL CIRCULATION IS NOT YET ESTABLISHED ACROSS E PORTIONS OF THE BASIN. HOWEVER...A WEAK TROUGH DOES CURRENTLY EXIST AND EXTENDS FROM 07N83W TO 05N92W TO 06N102W... WHERE IT TRANSITIONS TO ITCZ...CONTINUING ON TO 08N113W TO BEYOND 05N140W. SCATTERED MODERATE TO STRONG CONVECTION NOTED FROM 03N TO 07.5N E OF 91W. SCATTERED MODERATE TO STRONG CONVECTION NOTED FROM 90 NM S TO 240 NM N OF ITCZ W OF 111W. A SURFACE TROUGH IS ALONG THE COAST OF COLOMBIA FROM 04N77W TO 02N80W. ...DISCUSSION... A BROAD UPPER LEVEL TROUGH COVERS MOST OF THE AREA N OF 20N THIS MORNING...WITH A BLOCKING REX PATTERN CENTERED ALONG ABOUT 120W...WHERE A DEEP LAYERED CYCLONE WAS LOCATED NEAR 33.5N120W. A TROPICAL UPPER JETSTREAM CAN BE SEEN EXTENDING FROM SE OF THE HAWAIIAN ISLANDS NEAR 18N150W EAST NORTHEASTWARD ACROSS THE AREA THEN ACROSS N CENTRAL MEXICO. SEVERAL IMPULSES ARE EMBEDDED WITHIN THE JET...WITH MOST PROMINENT NOW APPROACHING THE S PORTION OF BAJA CALIFORNIA. UPPER LEVEL SPEED DIVERGENCE ASSOCIATED WITH THE JET IS ACTING TO ENHANCE A BROAD REGION OF ACTIVE CONVECTION ALONG THE ITCZ BETWEEN 125W AND 160W. UPPER RIDGING GENERALLY PREVAILS SE OF THE JET AND EXTENDS E ACROSS SE MEXICO AND INTO THE NW CARIBBEAN. TRADEWIND FLOW...A COLD FRONT THAT EXTENDS FROM THE FAR NE PACIFIC TO NEAR 34N140W IS MOVING SLOWLY SE TOWARDS NW PORTIONS OF THE AREA AND WILL SHIFT S INTO NW PORTIONS DURING THE EVENING HOURS AND GRADUALLY BECOME ILL DEFINED THROUGH WED. THE DEEP LAYERED CYCLONE NEAR 33.5N120W HAS PRODUCED A SURFACE TROUGH FROM SOUTHERN CALIFORNIA TO 28N130W. NORTHERLY SWELL MOVING INTO NE PORTIONS OF THE AREA FROM THE CALIFORNIA OFFSHORE WATERS HAS INCREASED WAVE HEIGHTS TO 8 TO 9 FT N OF 27N BETWEEN 128W AND 138W AND WILL INCREASE SLIGHTLY THERE OVER THE NEXT 2 DAYS. A 1032 MB HIGH PRES CENTER RESIDES NW OF THE COLD FRONT NEAR 41N144W THIS MORNING...AND IS INDUCING SUFFICIENT PRES GRADIENT N OF THE ITCZ TO GENERATE FRESH NE TRADEWINDS S OF A LINE FROM 20N120W TO 30N140W. 20-25 KT TRADEWINDS WERE OCCURRING W OF LINE FROM 07.5N140W TO 10N134W TO 16N140W THIS MORNING...WHERE SEAS WERE RUNNING 8 TO 10 FT IN A BROAD MIX OF SWELL. THE HIGH WILL SHIFT SE OVER THE NEXT 48 HOURS BEHIND THE COLD FRONT...AND ACT TO EXPAND THE AREA OF FRESH TRADEWINDS SLIGHTLY EASTWARD...WHERE SEAS SHOULD REMAIN 8 TO 11 FT. E OF 120W...WINDS S OF 15N ARE LIGHT TO MODERATE FROM VARYING DIRECTIONS...WITH SIGNS THAT A WEAK MONSOONAL CIRCULATION IS GRADUALLY DEVELOPING ACROSS THE FAR EASTERN PACIFIC. THE GULF OF CALIFORNIA...S TO SW WINDS OF 20 TO 25 KNOTS HAVE DEVELOPED THIS MORNING ACROSS N PORTIONS N OF 30N ACROSS THE GULF IN RESPONSE TO THE DEEP LAYERED CYCLONE AND SURFACE TROUGH EXTENDING FROM SOUTHERN CALIFORNIA. SEAS ARE BEING LIMITED TO 4- 6 FT THIS MORNING THERE DUE TO THE SMALL AREA AVAILABLE FOR WAVE GROWTH. THESE CONDITIONS WILL GENERALLY PREVAIL THROUGH 24 HOURS BEFORE WINDS DROP OFF DURING THE DAY WEDNESDAY THEN INCREASE AGAIN TO 20-25 KT WEDNESDAY NIGHT. THE GULF OF PAPAGAYO...GAP WINDS ARE EXPECTED TO PULSE TO 15-20 KT ACROSS THE GULF OF PAPAGAYO AND DOWNSTREAM TONIGHT AND THEN INCREASE FURTHER TO 20-25 KT WED NIGHT THROUGH THU MORNING...WHEN SEAS WILL BUILD TO 6-8 FT. $$ STRIPLING