000 AXPZ20 KNHC 080233 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC FRI MAY 08 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 0215 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... SCATTEROMETER WINDS INDICATE THAT THE ITCZ FORMS NEAR 02N92W AND EXTENDS NW THROUGH THE BASE OF AN EMBEDDED TROUGH AT 09N115W...CONTINUING W THROUGH ANOTHER EMBEDDED TROUGH AT 09N136W...THEN TURNS SW TO BEYOND 07N140W. ISOLATED MODERATE TO STRONG CONVECTION IS NOTED WITHIN 60 NM EITHER SIDE OF A LINE FROM 05N82W TO 01N90W TO 01N108W. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS OBSERVED WITHIN 180 NM EITHER SIDE OF A OF LINE FROM 05N105W TO 10N116W TO 10N128W TO 04N140W. ...DISCUSSION... AN UPPER TROUGH EXTENDS SW FROM SOUTHERN CALIFORNIA AT 34N119W TO 21N132W. AN UPPER ANTICYCLONE IS CENTERED OVER THE TROPICS AT 14N106W WITH AN UPPER RIDGE EXTENDING W TO A CREST AT 10N134W...AND ENHANCING CONVECTION ALONG THE ITCZ BETWEEN 106- 135W. AN UPPER RIDGE ALSO EXTENDS E FROM THE ANTICYCLONE TO A CREST NEAR 11N87W. A SHORTWAVE RIDGE EXTENDS NNE ACROSS EASTERN MEXICO TO A CREST OVER CENTRAL LOUISIANA. AN UPPER TROUGH EXTENDS S ACROSS THE WESTERN CARIBBEAN FROM CENTRAL CUBA TO ACROSS PANAMA TO A BASE OVER THE DEEP TROPICAL PACIFIC AT 06N82W. ITCZ DEBRIS MOISTURE IS ADVECTED NE WITHIN 390 NM OF A LINE FROM 12N118W TO OVER N-CENTRAL MEXICO AT 24N101W. ELSEWHERE AT THE LOW LEVELS A SURFACE RIDGE EXTENDS FROM 33N140W TO 13N92W. THE SURFACE TROUGH EMBEDDED IN THE ITCZ FROM 07N114W TO 12N116W IS FORECAST TO DISSIPATE ON FRI. THE SURFACE TROUGH EMBEDDED WITHIN THE ITCZ FROM 07N136W TO 11N134W WILL GRADUALLY FILL AS IT CROSSES 140W ON FRI. THE GRADIENT SW OF THE RIDGE IS SUPPORTING 20-25 KT NE TRADES ACROSS THE WATERS FROM 09-20N BETWEEN 120-140W. THE ASSOCIATED NE SWELL IS MIXING WITH LONG PERIOD S AND NW SWELL RESULTING IN COMBINED SEAS OF 8-12 FT. THE GRADIENT WILL GRADUALLY RELAX THROUGH SAT NIGHT WITH THE WINDS DIMINISHED TO 15-20 KT ON SUN. THE ENHANCED SEAS OF 7-9 FT WILL GRADUALLY SUBSIDE TO 6-7 FT LATE TUE. FRESH NW-N WINDS WILL CONTINUE ACROSS THE SUBTROPICAL WATERS NE OF THE RIDGE THROUGH FRI EVENING THEN DIMINISH TO MODERATE BREEZE. LONG PERIOD NW SWELL HAS BEEN MIXING WITH LONG PERIOD SOUTHERLY SWELL...AND MAINTAINING 7-9 FT COMBINED SEAS...ACROSS THE WATERS N OF THE RIDGE. THE NW SWELL WILL SUBSIDE ON FRI WITH 5-7 FT SEAS EXPECTED N OF THE RIDGE LATE SAT. ANOTHER BATCH OF LONG PERIOD SOUTHERLY SWELL HAS PROPAGATED INTO THE DISCUSSION WATERS S OF 02N BETWEEN 100-127W IN THE FORM OF 7- 9 FT COMBINED SEAS. RE-ENFORCING S SWELL WILL ARRIVE SUN NIGHT WITH SEAS OF 8-9 FT BUILDING S OF 10N E OF 120W ON MON NIGHT AND TUE...THEN SUBSIDING FROM THE N ON WED. GULF OF CALIFORNIA...A WEAK SURFACE LOW ALONG A TROUGH OVER THE NORTHERN GULF OF CALIFORNIA WILL MEANDER THROUGH FRI...AND MOVE E OVER EXTREME NW MEXICO ON FRI NIGHT. THE GRADIENT WILL SUPPORT S-SW 20-25 KT PULSES WITHIN ABOUT 90 NM E OF THE TROUGH AXIS AND WITHIN ABOUT 90 NM OVER THE S SEMICIRCLE OF THE LOW. THE LIMITED FETCH SHOULD ONLY ALLOW SEAS TO BUILD TO A MAXIMUM OF 7 FT. GUIDANCE IS SUGGESTING THE GRADIENT NE OF THE PACIFIC RIDGE WILL SUPPORT NW WINDS OF 20-25 KT ALONG THE PACIFIC COAST OF THE BAJA PENINSULA ON FRI EVENING THROUGH SAT NIGHT. GULF OF PAPAGAYO...GUIDANCE INDICATES NE-E 20-25 KT WINDS OVER AND JUST SW OF THE GULF OF PAPAGAYO TONIGHT. $$ NELSON