000 AXPZ20 KNHC 032151 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 2205 UTC THU JUL 03 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1945 UTC. ...SPECIAL FEATURES... TROPICAL DEPRESSION DOUGLAS IS CENTERED NEAR 20.6N 116.8W...OR ABOUT 410 NM W-SW OF THE SOUTHERN TIP OF BAJA CALIFORNIA AT 03/2100 UTC MOVING NW OR 315 DEGREES AT 2 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1006 MB. MAXIMUM SUSTAINED WIND SPEED IS 30 KT WITH GUSTS TO 40 KT. SCATTERED MODERATE CONVECTION WAS NOTED WITHIN 90 NM SE SEMICIRCLE AND 30 NM NW SEMICIRCLE OF CENTER. AN INCREASE IN FORWARD SPEED IS EXPECTED TO BEGIN TONIGHT AND SHOULD CONTINUE THROUGH SAT. ADDITIONAL WEAKENING IS FORECAST...AND DOUGLAS IS EXPECTED TO DEGENERATE INTO A REMNANT LOW BY FRI. PLEASE SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP4/WTPZ24 KNHC FOR MORE DETAILS. ...TROPICAL WAVES... A TROPICAL WAVE WAS ANALYZED FROM 12N95W THROUGH THE WESTERN GULF OF TEHUANTEPEC AND INLAND THROUGH S MEXICO INTO THE GULF OF MEXICO. THIS WAVE IS MOVING W AROUND 20 KT. SCATTERED MODERATE CONVECTION WAS NOTED E OF THE WAVE AXIS FROM 10N TO 15N BETWEEN 91W AND 95W. A SECOND TROPICAL WAVE WAS ANALYZED FROM 10N88W THROUGH THE GULF OF FONSECA INTO THE NW CARIBBEAN. THIS WAVE IS MOVING W AROUND 15-20 KT. SCATTERED MODERATE CONVECTION WAS WITHIN 90 NM W OF THE WAVE AXIS FROM 11N TO 13N. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH AXIS WAS ANALYZED FROM 09N78W TO 10N90W TO 08N98W TO 11N107W TO 10N110W THEN CONTINUES FROM 14N117W TO 10N127W. THE ITCZ AXIS WAS ANALYZED FROM 10N127W TO 11N132W TO 10N140W. SCATTERED MODERATE CONVECTION WAS WITHIN 240 NM S OF THE AXIS BETWEEN 80W AND 86W...WITHIN 240 NM N OF THE AXIS BETWEEN 97W AND 101W...AND FROM 04N TO 09N BETWEEN 110W AND 118W. SCATTERED MODERATE WITH ISOLATED STRONG CONVECTION WAS WITHIN 330 NM S OF THE AXIS BETWEEN 102W AND 107W. ...DISCUSSION... A 1026 MB SUBTROPICAL HIGH WAS ANALYZED NEAR 38N138W AND EXTENDS A RIDGE THROUGH 32N130W INTO THE CENTRAL GULF OF CALIFORNIA NEAR 28N112W. AN UPPER LOW NEAR 21N135W HAS DISRUPTED THE DEEP-LAYER RIDGING OVER THE AREA. THE PRESSURE GRADIENT BETWEEN THE HIGH AND THE MONSOON TROUGH/ITCZ IS ONLY TIGHT ENOUGH TO SUPPORT MODERATE WITH LOCALLY FRESH TRADE WINDS AS A RESULT. THE RIDGE EXTENDS N OF TROPICAL DEPRESSION DOUGLAS. CONDITIONS DIRECTLY ASSOCIATED WITH DOUGLAS ARE DESCRIED IN THE SPECIAL FEATURES SECTION ABOVE. SOUTHERLY FLOW ON THE EAST SIDE OF DOUGLAS HAS TRANSPORTED LOW LEVEL MOISTURE THROUGH THE GULF OF CALIFORNIA WITH PRECIPITABLE WATER VALUES GENERALLY AROUND 2 INCHES. THIS MOISTURE IS HELPING TO FUEL AFTERNOON THUNDERSTORMS OVER THE SIERRA MADRE OCCIDENTAL AND BAJA CALIFORNIA SUR. THE LEADING EDGE OF THE NEXT CROSS-EQUATORIAL SOUTHERLY SWELL TRAIN IS APPROACHING THE COAST OF CENTRAL AMERICA WITH PERIODS IN THE 20-22 SECOND RANGE. THIS SWELL WILL REACH THE COAST OF COSTA RICA AND WESTERN PANAMA THIS EVENING AND SPREAD NORTHWARD THROUGH FRI NIGHT...BRINGING ROUGH SURF CONDITIONS. GAP WINDS... GULF OF PAPAGAYO...THE ATLANTIC SUBTROPICAL RIDGE WILL BUILD WESTWARD TO THE S OF ATLANTIC HURRICANE ARTHUR OVER THE NEXT 24 HOURS...INCREASING THE TRADE WINDS IN THE WESTERN CARIBBEAN. FRESH TO STRONG WINDS WILL FUNNEL THROUGH THE GULF OF PAPAGAYO INTO THE PACIFIC OVERNIGHT TONIGHT. THE PRESSURE GRADIENT WILL RELAX ON FRIDAY...WITH WINDS DIMINISHING BELOW 25 KT BY FRI AFTERNOON. GULF OF TEHUANTEPEC...PRESSURES WILL RISE OVER THE GULF OF MEXICO BEHIND A COLD FRONT CURRENTLY DRAPED OVER THE N CENTRAL GULF OF MEXICO. THIS WILL INCREASE THE PRESSURE GRADIENT BETWEEN THE HIGH TO THE NORTH AND THE MONSOON TROUGH TO THE SOUTH...FORCING N-NE WINDS TO FUNNEL THROUGH THE GULF OF TEHUANTEPEC. WINDS WILL PULSE TO A FRESH TO STRONG BREEZE EARLY FRI MORNING AND EARLY SAT MORNING AS DRAINAGE FLOW OFF THE LAND ENHANCES THE WINDS. $$ SCHAUER