000 AXPZ20 KNHC 181503 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC FRI JUL 18 2014 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 1500 UTC. ...TROPICAL WAVES... A TROPICAL WAVE EXTENDS FROM 05N100W TO 13N100W. THE SURFACE DEPICTION OF THE WAVE WAS REPOSITIONED A LITTLE FARTHER SOUTHWARD ON THE 12 UTC ANALYSIS TO ACCOUNT FOR PROFOUND SURFACE RIDGING TO THE NORTH NOTED IN EARLIER ASCAT SATELLITE WIND DATA. WHILE NOT HIGHLY AMPLIFIED...DIAGNOSTIC TOOLS SUGGEST THE WAVE IS IN AN AREA CONDUCIVE TO WAVE GROWTH. A LARGE AREA OF SHOWERS AND THUNDERSTORMS ARE NOTED OVER THE SOUTHERN PORTION OF THE WAVE NEAR THE MONSOON TROUGH. THE ECMWF MAINTAINS GOOD CONTINUITY IN THE LOWER TO MID LEVELS OF THE ATMOSPHERE SHOWING THE WAVE AS A FAIRLY LOW LATITUDE SYSTEM MIGRATING WEST AT 10 TO 15 KT OVER THE NEXT SEVERAL DAYS. THE GFS ALSO SHOWS GOOD CONTINUITY IN THE SHORT TERM...BUT DAMPENS OUT THE WAVE WEST OF 120W EARLY NEXT WEEK. A TROPICAL WAVE EXTENDS FROM 07N118W TO 14N118W. THIS WAVE CONTINUES TO SHOW A DECENT SURFACE DEPICTION...AS NOTED IN AN ASCAT SATELLITE PASS FROM 0542 UTC. WHILE THERE APPEAR TO BE NO SIGNIFICANT WINDS ASSOCIATED WITH THIS WAVE...A EARLY MORNING FEW SHOWERS ARE OBSERVED AT THE BASE OF THE TROPICAL WAVE NEAR THE MONSOON TROUGH. THE WAVE IS MOVING INTO AN AREA OF DEEP LAYER DRY AIR ON THE WESTERN EDGE OF AN UPPER TROUGH...AND WILL BECOME DECOUPLED FROM THE CONVECTION THROUGH TONIGHT. THE GFS SHOWS THE TROPICAL WAVE DAMPENING OUT IN THE LOWER TO MID LEVELS AS IT MOVES THROUGH 130W THIS WEEKEND...IN CONTRAST TO THE ECMWF WHICH INDICATES A MORE IN TACT SYSTEM. EITHER WAY...NO SIGNIFICANT SENSIBLE WEATHER IS ANTICIPATED AT THE SURFACE ASSOCIATED WITH THE TROPICAL WAVE OVER THE NEXT SEVERAL DAYS. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM 08N78W TO 09N120W. THE ITCZ EXTENDS FROM 09N120W TO 08N130W TO 12N135W. NUMEROUS STRONG CONVECTION WAS OBSERVED N OF 06N E OF 82W. SCATTERED MODERATE TO STRONG CONVECTION WAS OBSERVED WITHIN 120 NM N AND 180 NM S OF AXIS BETWEEN 97W TO 102W. ...DISCUSSION... AN UPPER CYCLONE PERSISTS NEAR 24N116W DRIFTING NNW WITH A TROUGH AXIS REACHING TO 13N116W. ASSOCIATED LIFT AND DEEP LAYER MOISTURE ON THE SOUTHEAST SIDE OF THE UPPER CYCLONE/TROUGH IS SUPPORTING A WEAK SURFACE TROUGH ALONG 108W SOUTH OF 13N...AS WELL AS CONVECTION ALONG THE TROPICAL WAVE NEAR 118W. DEEP LAYER DRY AIR IS PUSHING SOUTHWARD ALONG THE WEST SIDE OF THE UPPER CYCLONE/TROUGH...REACHING AS FAR SOUTH AS 10N NEAR 120W. THIS IS LARGELY SUPPRESSING CONVECTIVE DEVELOPMENT ALONG THE ITCZ BETWEEN 120W AND 135W. EAST TO WEST ORIENTED WEAK RIDGING PERSISTS ALONG ROUGHLY 25N...MAINTAINING GENERALLY MODERATE TRADE WINDS S OF 20N. SLIGHTLY STRONGER WINDS WITH SEAS TO 9 FT CONTINUE NEAR 14N140W...ON THE OUTER PERIPHERY OF T.S. WALI LOCATED WEST OF THE DISCUSSION AREA NEAR 15N142W. PLEASE SEE LATEST BULLETIN WTPA21 PHFO/TCMCP1 FROM THE CENTRAL PACIFIC HURRICANE CENTER FOR FURTHER DETAILS ON WALI. WINDS AND SEAS E OF 140W WILL DIMINISH THROUGH LATE TODAY. FARTHER EAST...STRONG CONVECTION IS AGAIN OBSERVED OVER THE GULF OF PANAMA. THIS IS SIMILAR TO YESTERDAY MORNING...WHEN ACTIVITY FLARED IN THIS AREA AT THE BASE OF A SHARP UPPER TROUGH THAT HAS SINCE CUT OFF INTO AN UPPER CYCLONE OVER THE SW CARIBBEAN. THE THUNDERSTORMS WILL LIKELY DIMINISH THROUGH LATE TODAY WITH DIURNAL TRENDS...BUT MAY FLARE AGAIN OVERNIGHT AS THE UPPER CYCLONE SEEMS TO REMAIN IN PLACE ALTHOUGH WEAKENING. $$ CHRISTENSEN