000 AXPZ20 KNHC 160933 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC MON JUN 16 2008 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0915 UTC. ...ITCZ... INTERTROPICAL CONVERGENCE ZONE ALONG 05N77W TO 08N86W TO 09N100W TO 05N120W TO 06N140W. SCATTERED MODERATE ISOLATED STRONG WITHIN 150 NM EITHER SIDE OF AXIS BETWEEN 77W AND 82W. SCATTERED MODERATE WITHIN 120 NM N OF AXIS BETWEEN 93W AND 97W. SCATTERED MODERATE WITHIN 210 NM N OF AXIS BETWEEN 107W AND 110W. ...DISCUSSION... A STRONG PRES GRADIENT BETWEEN CLIMATOLOGICAL LOW PRESSURE OVER THE DESERT SW AND HIGH PRESSURE BUILDING BEHIND THE LAST SIGNIFICANT SHORTWAVE TROUGH TO MOVE INTO THE NORTHWEST CONUS HAS BEEN GENERATING GALE CONDITIONS OFFSHORE THE CALIFORNIA AND OREGON COASTS SINCE LATE FRI LAST WEEK. EVEN THOUGH GALE CONDITIONS CONTINUE OVER THESE AREAS...LATEST QUIKSCAT DATA AND SHIP REPORTS INDICATE THAT NW TO N WINDS TO 20 KT REMAIN N OF 31N. AS A RESULT OF THE SUSTAINED GALE FORCE WINDS...SEAS HAVE LOCALLY BUILT TO AS 15 FT JUST N OF THE AREA...AND ASSOCIATED N SWELL HAS JUST RECENTLY BEGUN TO ARRIVE OVER THE FAR NORTHERN WATERS GENERALLY N OF 29N BETWEEN 125W AND 134W. OVER THE NEXT FEW DAYS...MODEL GUIDANCE INDICATES THAT NORTHERLY SWELL SHOULD CONTINUE TO AFFECT THE NORTHERN WATERS AS FAR S AS 25N BETWEEN 125W AND 135W AND COMBINE WITH LONGER PERIOD SW SWELL WITH ORIGINS FROM THE SOUTHERN HEMISPHERE. PEAK SEAS WILL LIKELY OCCUR DURING THE DAY TUE WITH A SLOW SUBSIDING OF SEAS BY MID-WEEK. FARTHER SOUTH...TWO WELL-DEFINED SWELL TRAINS...ONE FROM THE SE AND ONE FROM THE SWELL...HAVE BEEN PROPAGATING OUT OF THE SOUTHERN HEMISPHERE AND CROSSING THE EQUATOR THE PAST FEW DAYS. AS THEY ARRIVE...A LARGE AREA OF 8 TO 10 FT SEAS HAS DEVELOPED ...GENERALLY S OF 15N W OF 128W AND S OF 13S BETWEEN 93W AND 128W. IN ADDITION TO THE SWELL...A 0304 UTC QUIKSCAT IMAGE SHOWED A SMALL AREA OF NE 20 KT FROM 09N TO 16N W OF 134W...SUGGESTING THAT NE WIND WAVES HAVE COMBINED WITH SE AND SW SWELL OVER THIS AREA. NOAA WAVEWATCH III GUIDANCE SUGGESTS THAT THE SWELL WILL GRADUALLY SUBSIDE OVER THE NEXT FEW DAYS. HOWEVER...A LARGE AREA OF AROUND 8 TO 9 FT SEAS SHOULD STILL COVER THE SOUTHERN WATERS WITH INTERMITTENT 20 KT NORTHEASTERLY WINDS NEAR THE WESTERN BORDER. ELSEWHERE...STRONG TRADES IN THE CENTRAL AND EASTERN CARIBBEAN MAY EVENTUALLY SPARK A GAP WIND EVENT IN THE GULF OF PAPAGAYO LATER THIS WEEK. ALTHOUGH CURRENT GUIDANCE SHOWS NO THREAT OF THIS THROUGH MID-WEEK...THERE IS SOME CHANCE OF OBSERVING TRANSIENT PERIODS OF NE TO E WINDS UP TO 20 KT DOWNSTREAM OF THIS AREA. MODELS DO...HOWEVER...INDICATE A BETTER CHANCE OF A MORE SUSTAINED GAP WIND EVENT BY THU OR FRI. FINALLY...REAL-TIME NCEP RE-ANALYSIS DATA INDICATE ANOMALOUS CYCLONIC CIRCULATIONS AT UPPER-LEVELS EITHER SIDE OF THE DATE- LINE AROUND 20N AND 20S. A STREAM OF ANOMALOUS WESTERLY FLOW ASSOCIATED WITH THESE FEATURES...WITH ANOMALIES OF OF 20 TO 60 KT ABOVE CLIMATOLOGY...EXTENDS FROM THE DATELINE TO FAR E AS 120W. THE STRONG WESTERLY FLOW PRECEDES A MODERATELY STRONG MADDEN-JULIAN OSCILLATION /MJO/ CURRENTLY ORGANIZING OVER THE INDIAN OCEAN...WHICH IS SLOWLY HEADING EAST. ALTHOUGH THE EXACT DETAILS ARE ELUSIVE AT THIS TIME...THE CURRENT MJO SHOULD SPREAD ACROSS THE REMAINDER OF THE INDIAN OCEAN AND WESTERN PACIFIC IN THE NEXT WEEK OR TWO...LIKELY RESULTING IN AN INCREASE IN THE CHANCE OF TROPICAL CYCLONE ACTIVITY. THE EXPECTATION IS THAT A SIMILAR INCREASE IN THE CHANCE OF TROPICAL CYCLONE ACTIVITY SHOULD EVENTUALLY REACH THE TROPICAL EASTERN PACIFIC TOWARD THE VERY END OF JUNE OR THE FIRST WEEK OF JULY. $$ KIMBERLAIN