000 AXPZ20 KNHC 252204 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 2205 UTC SAT MAY 25 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2145 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... MONSOON TROUGH AXIS EXTENDS FROM 09N84W TO LOW PRES NEAR 09N90W 1010 MB TO LOW PRES NEAR 10N99W 1010 MB TO LOW PRES NEAR 10N108W 1010 MB TO 10N117W TO 09N126W. ITCZ AXIS EXTENDS FROM 09N126W TO 07N140W. SCATTERED MODERATE CONVECTION IS WITHIN 120 NM S OF AXIS BETWEEN 111W-119W. ...DISCUSSION... ALOFT...AN UPPER LEVEL TROUGH STRETCHES FROM THE FAR PACIFIC NW SECTION OF THE U.S. SW THROUGH 32N135W TO A RECENTLY FORMED UPPER LOW NEAR 28N137W. TO ITS SE...BROAD ANTICYCLONIC WITH THE MEAN ANTICYCLONE SITUATED AT 16N115W COVERS THE AREA BETWEEN THE TROUGH AND ANOTHER UPPER LEVEL TROUGH JUST EXITED THE AREA TO OVER CENTRAL MEXICO. THE UPPER FLOW PATTERN BETWEEN THE WRN MOST TROUGH AND THE ANTICYCLONE IS ADVECTING DEEP TROPICAL MOISTURE ...IN THE FORM OF SCATTERED TO BROKEN HIGH CLOUDS...FROM THE CENTRAL PACIFIC NEWD TO ACROSS THE FAR WRN AND N CENTRAL PORTIONS OF THE DISCUSSION WITH A TRAJECTORY TOWARDS SRN CALIFORNIA. OTHERWISE...MOSTLY MODERATE SUBSIDENCE COVERS THE AREA WITHIN THE AREA OF BROAD ANTICYCLONE FLOW MAINTAINING RATHER DRY AND STABLE CONDITIONS OVER THAT PORTION OF THE AREA AS NOTED BY THE FIELD OF SCATTERED TO BROKEN STRATOCUMLUS CLOUDS PRESENT TO THE N OF 13N BETWEEN 115W AND 120W...AND ALSO UNDERNEATH THE SCATTERED TO BROKEN HIGH CLOUDS STREAMING NEWD AS MENTIONED ABOVE. THE AFOREMENTIONED UPPER TROUGH ACROSS THE NW PORTION OF THE AREA WILL TRANSLATED EWD TO THE NE PORTION OF THE AREA BY MON...WITH THE ASSOCIATED UPPER LOW SHEARING OFF TO SW OF THE AREA...HOWEVER NO SIGNIFICANT WEATHER IS EXPECTED WITH THESE FEATURES. OVER THE ERN PORTION OF THE AREA...AN UPPER ANTICYCLONE IS LOCATED IN THE VICINITY OF THE GULF OF TEHUANTEPEC WITH ITS BROAD ENVELOP OF ANTICYCLONIC FLOW COVERING THE AREA TO THE N OF 10N AND E OF ABOUT 106W. LATEST WATER VAPOR IMAGERY SHOWS ABUNDANT MOISTURE IN THE MID AND UPPER LEVELS OF THE ATMOSPHERE OVER THIS PORTION OF THE AREA WITH MODERATE TO STRONG NE WINDS ALONG THE SRN PERIPHERY OF THE ANTICYCLONIC SHIELD. AT THE SURFACE TO LOW LEVELS WITHIN THIS SAME PORTION OF THE AREA... MOISTURE IS OBSERVED IN THE FORM OF CLUSTERS OF SCATTERED SHOWERS AND TSTMS. THIS ACTIVITY IS BEING AIDED BY THE ANTICYCLONIC FLOW PRESENT ALOFT...HOWEVER POCKETS OF DRY AIR OR NOTED AS WELL IN BETWEEN THE ACTIVITY. AS DESCRIBED UNDER THE ITCZ/MONSOON TROUGH SECTION...THERE CONTINUES TO BE THREE SMALL LOW PRES FEATURES EMBEDDED WITHIN THE MONSOON TROUGH. THE FIRST AT 09N90WW...THE SECOND AT 10N99W AND THE THIRD AT 10N108W... ALL WITH PRES OF 1010 MB. THESE LOWS MAKE UP PARTS OF THE OBSERVED CLUSTERS OF SHOWERS AND TSTMS. THE LOW AT 09N90W IS NOTED WITH ASSOCIATED SCATTERED MODERATE/ISOLATED STRONG CONVECTION WITHIN 45 NM OF 12N88W. THE LOW AT 10N108W IS NOTED WITH SCATTERED MODERATE /ISOLATED STRONG CONVECTION FROM 09N TO 13N BETWEEN 104W AND 108W...AND ALSO FROM 09N TO 13N BETWEEN 108W AND 110W. THE SECOND LOW ONLY HAS ISOLATED TO WIDELY SCATTERED SHOWERS AND TSTMS WITHIN 90 NM OF THE CENTER. THESE LOWS AS WELL AS THE SURROUNDING SHOWER AND TSTM ACTIVITY REMAIN DISORGANIZED IN NATURE...BUT MODEL GUIDANCE CONTINUES TO SUGGEST THAT SOME SLOW DEVELOPMENT IS POSSIBLE WITH THERE LOWS OVER THE NEXT COUPLE OF DAYS. SEE LATEST TROPICAL WEATHER OUTLOOKS FOR PROBABILITY CONDITIONS RELATING TO THESE LOW PRES FEATURES. AT THE SURFACE...A 1030 MB HIGH IS ANALYZED NW OF THE AREA AT 34N141W WITH A RIDGE EXTENDING SEWD TO NEAR 21N116W. THE ASCAT PASS FROM 1742W UTC THIS AFTERNOON REVEALED NE TRADES OF 15-20 KT ACROSS THE WATERS FROM 10N TO 21N AND W OF 122W WITH SEAS THERE TO 9 FT IN NW TO N SWELL. THESE CONDITIONS WILL SHIFT TO N OF 23N BETWEEN 116W AND 121W BY MON AFTERNOON WITH SEAS TO 9 FT IN MERGING SW AND NW SWELL. LONG PERIOD CROSS EQUATORIAL SW SWELLS AT 16-18 SECONDS DOMINATE MOST OF THE FORECAST WATERS E OF 115W...WHILE LONG PERIOD NW SWELLS ARE SPREADING ACROSS THE NRN PORTION. THESE SWELL EVENTS ARE FORECAST TO MERGE TONIGHT AND SUN. $$ AGUIRRE