000 AXPZ20 KNHC 271605 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC WED JUL 27 2011 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 1545 UTC. ...ITCZ/MONSOON TROUGH... MONSOON TROUGH EXTENDS WNW FROM COSTA RICA AT 8N84W TO 9N94W TO 12N110W TO 11N117W TO 10N133W...WHERE LOW LEVEL WINDS INDICATE THAT THE ITCZ AXIS BEGINS AND CONTINUES W TO BEYOND 8N140W. OVERCAST MULTILAYERED CLOUDS ARE OBSERVED FROM 10N TO THE EQUATOR BETWEEN 78W AND 100W. LOCALLY BROKEN MULTILAYERED CLOUDS ARE OBSERVED FROM 02N 14N BETWEEN 100W AND 135W. SCATTERED MODERATE ISOLATED STRONG CONVECTION EXISTS FROM 5N-9N BETWEEN 85W-92W. SCATTERED MODERATE CONVECTION IS WITHIN 120 NM N OF THE MONSOON TROUGH BETWEEN 118W-124W. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS OVER THE FAR EASTERN PORTION OF THE AREA FROM 3N-8N E OF 79W. ...DISCUSSION... AN UPPER RIDGE EXTENDS SW FROM THE MIDWEST REGION OF THE U.S. SW TO A CREST AT 31N125W. TO ITS NW AN UPPER LEVEL TROUGH EXTENDS FROM CENTRAL CALIFORNIA SW TO 30N131W...AND CONTINUES NW TO 32N140W. THIS TROUGH BISECTS A N TO S UPPER RIDGE THAT IS ANCHORED BY AN UPPER LEVEL ANTICYCLONE MOVING SEWD N OF THE AREA NEAR 37N137W...AND ANOTHER ONE IN THE AREA NEAR 25N137W. SATELLITE WATER VAPOR IMAGERY SHOWS ABUNDANT MODERATE SUBSIDENCE AND ASSOCIATED DRY STABLE AIR COVERING THE AREA N OF 19N W OF AND W OF ABOUT 121W. THE RIDGE IS FORECAST TO BUILD WESTWARD SOME OVER THE NEXT 48 HOURS BLOCKING THE UPPER TROUGH FROM ADVANCING TOO FAR TO THE SE RESULTING IN A CUT OFF CYCLONE TO FORM NEAR 26N130W LATE TONIGHT AND MEANDER THROUGH FRI. AN UPPER ANTICYCLONE IS S OF THE EQUATOR NEAR 03S95W WITH A RIDGE EXTENDING W ALONG THE EQUATOR TO A SHARP CREST AT 126W. THIS SETS UP A LARGE AREA OF UPPER DIFFLUENCE OVER THE MONSOON TROUGH AND ITCZ WITH CONVECTION THERE SLIGHTLY ENHANCED AS PREVIOUSLY DESCRIBED. THE RESULTANT DEBRIS MOISTURE IS FANNING OUT FROM 2N-17N BETWEEN 98W AND 120W...AND FROM 6N-16N BETWEEN 120W AND 139W. A SMALL BAND OF THE MOISTURE CONTINUES TO ADVECT NWD ALONG 124W...BUT EVAPORATES AS IT REACHES 24N AS IT ENCOUNTERS THE DRIER AIR MASS. AN UPPER LEVEL CYCLONE IS OVER THE SW GULF OF MEXICO WITH A TROUGH EXTENDING ACROSS MEXICO ALONG 21N INTO ANOTHER UPPER CYCLONE OVER THE PACIFIC AT 21N114W. ANOTHER UPPER CYCLONE IS OVER THE DEEP TROPICS AT 07N92W. AN UPPER RIDGE EXTENDS SW ACROSS GUATEMALA TO NEAR 13N102W. CONVECTION IS SLIGHTLY ENHANCED ALONG THE MONSOON TROUGH TO THE E OF 100W...WITH THE DEBRIS MOISTURE COVERING THE AREA E OF 93W. THERE IS SOME SIGNS OF BROAD CYCLONIC TURNING THERE...AND GLOBAL MODELS SUGGEST THAT LOW PRES WILL LINGER THERE THROUGH THE NEXT 48 HOURS. CROSS EQUATORIAL SE SWELLS...RESULTING IN SEAS TO 10 FT...ARE PROPAGATING N AND NE OVER THE WATERS TO THE S OF 11N BETWEEN 90W AND 125W AND ALSO S OF 5N BETWEEN 80W AND 87W...WITH THE SW SWELL TRAIN INTERRUPTED BY THE GALAPAGOS ISLANDS. THE SW MONSOON FLOW IS EXPECTED TO INCREASE TO 20 KT IN THE AREA BOUNDED BY 04N-08N BETWEEN 95W-95W LATE TONIGHT...AND SHIFT E TO THE AREA BOUNDED BY 4N-8N BETWEEN 80W AND 90W THU NIGHT... WITH LIGHTER WINDS AND SEAS POSSIBLY IN THE RANGE OF 8-10 FT IN SW SWELL ELSEWHERE S OF 14N AND E OF 105W. A LOW LEVEL TROUGH WILL DIP INTO THE NORTHERN WATERS FRI ALONG 31N128W TO 25N130W. THE TROUGH WILL BE PRECEDED THU NIGHT BY NORTHERLY WINDS TO 20 KT AND SEAS TO 9 FT DRIVEN BY A N SWELL OVER THE AREA N OF 28N AND W OF 125W. $$ AGUIRRE 22