000 AXPZ20 KNHC 160937 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC SAT MAY 16 2015 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 0830 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM 10N87W TO 06N100W TO 09N110W TO 06N115W TO LOW PRES NEAR 11N124W 1010 MB TO 07N130W TO 09N138W TO BEYOND 06N140W. SCATTERED MODERATE TO STRONG CONVECTION NOTED FROM 05N TO 10.5N E OF 84W...AND FROM 01.5N TO 10N BETWEEN 84W AND 91W. SCATTERED MODERATE ISOLATED STRONG CONVECTION NOTED WITHIN 120 NM N AND S OF AXIS TO 02N BETWEEN 93W AND 112W. SCATTERED TO LOCALLY NUMEROUS WITHIN 330 NM NE QUADRANT OF LOW PRES NEAR 11N124W. SCATTERED MODERATE TO STRONG CONVECTION NOTED WITHIN 90 NM N AND 210 NM S OF AXIS BETWEEN 117W AND 134W. ...DISCUSSION... A 1025 MB SUBTROPICAL HIGH CENTERED NEAR 31N147W EXTENDS A RIDGE E TO THE OFFSHORE WATERS OF SOUTHERN CALIFORNIA AND BAJA CALIFORNIA NORTE...THEN BRIDGES OVER A COLD FRONT THAT EXTENDS FROM 32N113.5W TO 30N114.5W TO 25N120W TO 24N130W...TO NEAR 18N108W. THE PRESSURE GRADIENT BETWEEN THIS RIDGE AND LOW PRES SYSTEMS EMBEDDED IN THE MONSOON TROUGH W OF 108W IS GENERATING FRESH NE TRADE WINDS AS OBSERVED BY RECENT ASCAT PASSES...GENERALLY FROM 10N TO 20N W OF 115W. TRADES ARE EXPECTED TO REMAIN A FRESH BREEZE OVER W WATERS N OF THE MONSOON TROUGH THROUGH THE FORECAST PERIOD AS A RIDGE WILL PERSIST IN THE GENERAL POSITION. THE COLD FRONT HAS MOVED SE ACROSS THE AREA AND INTO BAJA CALIFORNIA NORTE AND EXTREME PORTIONS OF THE GULF OF CALIFORNIA...AND WILL DIP S BY THIS EVENING AND REACH FROM CENTRAL PORTIONS OF THE BAJA PENINSULA TO NEAR 23N120W WHERE IT WILL DISSIPATE. A RECENT ASCAT PASS ACROSS THE GULF OF CALIFORNIA DEPICTED SW WINDS 20-25 KT N OF 29N AND SE OF THE FRONT...BUT SHOULD DIMINISH TO BELOW 20 KT LATER THIS MORNING. ELSEWHERE ACROSS THE PACIFIC WATERS...WINDS NEAR THE FRONT ARE EXPECTED TO REMAIN BELOW A FRESH BREEZE...WITH SEAS CURRENTLY 8- 11 FT BEHIND THE FRONT AND E OF 132W. HOWEVER SEAS WILL SUBSIDE TO LESS THAN 8 FT WITHIN THE NEXT 24 HOURS. THE RIDGE IS PROVIDING SUFFICIENT PRESSURE GRADIENT TO INDUCE FRESH NWLY WINDS ALONG THE PACIFIC COAST OF THE BAJA PENINSULA...AND NEAR 20 KT ACROSS THE NEAR SHORE WATERS S OF CABO SAN LAZARO...WHICH SHOULD DIMINISH TO NEAR 15 KT BY THIS EVENING. CONVECTION REMAINS ACTIVE IN THE VICINITY OF THE MONSOON TROUGH...AS DESCRIBED ABOVE...AS A SERIES OF EASTERLY WAVES CONTINUE TO PROPAGATE WESTWARD THROUGH THE REGION...TO PRODUCE ABUNDANT LOW LEVEL MOISTURE AND SPEED CONVERGENCE. CONVECTION ACROSS THIS REGION HAS DIMINISHED IN AREAL COVERAGE DURING THE PAST 24 HOURS...AND IS EXPECTED TO SHIFT E OF 120W DURING THE NEXT 24 HOURS AS THE BROAD UPPER RIDGE PROVIDING VENTILATION FOR THE DEEP CONVECTION BEGINS TO FLATTEN DUE TO AN APPROACHING SHORTWAVE ENTERING NW PORTIONS OF THE AREA THIS MORNING. GAP WINDS... GULF OF PAPAGAYO...THE PRESSURE GRADIENT BETWEEN RIDGING OVER THE NW CARIBBEAN AND LOWER PRESSURE ALONG THE MONSOON TROUGH IS SUPPORTING A STRONG BREEZE ACROSS THE GULF OF PAPAGAYO AND DOWNSTREAM TO 89W WITH THE ASSISTANCE OF NOCTURNAL DRAINAGE FLOW. THESE WINDS WILL DIMINISH BY NOON TIME...AND THEN REPEAT THIS SAME CYCLE OF INCREASING WINDS AND SEAS AGAIN TONIGHT AND SUNDAY NIGHT. $$ STRIPLING