000 AXPZ20 KNHC 110917 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC SUN SEP 11 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0900 UTC. ...ITCZ/MONSOON TROUGH... MONSOON TROUGH EXTENDS FROM THE SW CARIBBEAN ACROSS THE COSTA RICA-NICARAGUA BORDER...ENTERING THE EPAC WATERS NEAR 11N86W TO 20N111W TO LOW PRES 1008 MB NEAR 20N117W TO LOW PRES 1010 MB NEAR 14N132.5W TO 10N140W. SCATTERED MODERATE TO STRONG CONVECTION WAS NOTED WITHIN 120 NM OF AXIS E OF 90W. ...DISCUSSION... A WEAK HIGH PRES RIDGE CONTINUES ACROSS THE W AND NW PORTIONS OF THE AREA. A WEAK PRESSURE GRADIENT IS RESULTING IN NE TRADES AT LESS THAN 20 KT. TWO WEAK LOW PRESSURE CENTERS CONTINUE TO SPIN WITHIN THE MONSOON TROUGH. THE FIRST ONE IS CENTERED NEAR 13N132W. THERE IS VERY WEAK SHOWER ACTIVITY CURRENTLY ASSOCIATED WITH THIS FEATURE WITH A SMALL AREA OF 20 KT WINDS IN THE NW QUADRANT OF THE LOW. THIS LOW PRESSURE SYSTEM IS EXPECTED TO DISSIPATE WITHIN THE NEXT 24 HOURS. THE SECOND LOW PRESSURE AREA IS LOCATED NEAR 16N117W AS DEPICTED BY A WELL PLACED ASCAT PASS AT 0440 UTC. THE ASCAT PASS INDICATED A SMALL AREA OF WINDS TO 20 KT IN THE S QUADRANT OF THE LOW. THIS LOW HAS NO SIGNIFICANT CONVECTION ASSOCIATED WITH IT...IT WILL CONTINUE TO WEAKEN OVER THE REMAINDER OF THE FORECAST PERIOD. GULF OF CALIFORNIA...SOUTHERLY WINDS AT 15 TO 20 KT OVER THE WATERS N OF 30N WILL DIMINISH EARLY THIS MORNING. NORTHERLY SWELLS...RESULTING IN COMBINED SEAS OF 8 FT...PREVAIL OVER THE WATERS N OF 27N BETWEEN 120W AND 134W. THIS SWELL WILL SPREAD SLIGHTLY FURTHER S BEFORE SUBSIDING BELOW 8 FT MON NIGHT. CROSS EQUATORIAL SOUTHERLY SWELL...WITH SEAS TO 9 FT...PREVAILS S OF 06N BETWEEN 94W AND 133W. THIS SWELL WILL CONTINUE TO SPREAD NORTHWARD THROUGH THE FORECAST PERIOD. $$ AL