000
AXPZ20 KNHC 201608
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC SUN APR 20 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC. 
  
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
MONSOONAL CIRCULATION STILL NOT YET EVIDENT ACROSS THE AREA. 
ITCZ EXTENDS FROM 03N77W TO 05N89W TO 06N106W TO 03N117W TO 
03N130W TO BEYOND 04.5N140W. SCATTERED MODERATE TO STRONG 
CONVECTION NOTED WITHIN 60 NM N AND 210 NM S OF AXIS E OF 108W. 
SCATTERED TO LOCALLY NUMEROUS MODERATE TO STRONG CONVECTION 
NOTED WITHIN 210 NM N OF AXIS W OF 123W.


...DISCUSSION...                                                
THE LATEST WEATHER OBSERVATIONS AT 1445 UTC FROM SALINA CRUZ ON 
THE PACIFIC SIDE OF THE ISTHMUS OF TEHUANTEPEC INDICATED N WINDS 
AT 10 KT GUSTING TO 19 KT...AN INDICATION THE STRONG GAP FLOW 
HAS BEGUN TO SUBSIDE...AS FORECAST BY GLOBAL MODELS. A 0900 UTC  
SHIP REPORT BY THE JPO VELA PASSING WELL DOWNWIND FROM THE GULF 
OF TEHUANTEPEC INDICATED WINDS AROUND 30 KT...LIKELY THE PEAK OF 
THE OVERNIGHT DRAINAGE FLOW. WINDS AND SEAS WILL CONTINUE TO 
SUBSIDE QUICKLY THROUGHOUT THE AFTERNOON AND ARE EXPECTED TO 
FALL BELOW 20 KT WITH SEAS LESS THAN 8 FT BY THIS EVENING...WITH 
WINDS THEN BECOMING VARIABLE FOR THE NEXT SEVERAL DAYS.
 
FRESH GAP WIND FLOW ALSO THROUGH THE GULF OF PAPAGAYO THIS 
MORNING IS PULSING TO AROUND 20 KT WITH GUSTS TO 25 KT 
OVERNIGHT...BUT HAS BEGUN TO DIMINISH THIS MORNING. THE FRESH 
FLOW IS EXPECTED AGAIN TONIGHT INTO EARLY MON MORNING BEFORE 
DIMINISHING AFTER SUNRISE. 

ELSEWHERE AN UPPER TROUGH EXTENDING FROM THE SOUTHWEST UNITED 
STATES TO 20N120W WILL SHIFT EASTWARD ACROSS THE BAJA PENINSULA 
AND THE GULF OF CALIFORNIA THROUGH TONIGHT. UPPER FORCING ON THE 
SE SIDE OF THE TROUGH IS SUPPORTING SCATTERED CONVECTION FROM 
FROM 10N TO 14N BETWEEN 99W AND 109W.
 
1026 MB HIGH PRES IS CENTERED N OF THE AREA NEAR 35N131W...AND 
IS SHIFTING E AHEAD OF A LARGE AND STRONG FRONTAL SYSTEM MOVING 
ACROSS THE NE PACIFIC. THIS FRONT WILL REMAIN N OF THE AREA AND 
MOVE INTO THE PACIFIC COAST OF THE U.S. TONIGHT...WITH A STRONG 
PULSE OF NW SWELL MOVING THROUGH THE AREA WATERS TODAY THROUGH 
TUESDAY. SEAS AREA ALREADY 8-10 FT IN THIS NW SWELL NW OF LINE 
FROM 30N133W TO 26.5N140W AND WILL REACH CENTRAL PORTIONS OF THE 
AREA BY TUE MORNING.

FARTHER SOUTH...THE RIDGE IS SUPPORTING 20 TO LOCALLY 25 KT 
TRADE WIND FLOW FROM 09N TO 16N W OF 132W....WHERE TRADE WIND 
CONVERGENCE IS SUPPORTING SCATTERED MODERATE TO STRONG 
CONVECTION ALONG AND S OF THE ITCZ DESCRIBED ABOVE W OF 123W. A 
1030 MB HIGH WILL BUILD ACROSS THE AREA FROM THE NW LATE MON 
THROUGH TUE AND ACT TO BROADEN THE AREA OF FRESH TRADES FROM 
08.5N TO 17N W OF 135W BY TUE MORNING. 
 
NORTHERLY WINDS OFF THE PACIFIC COAST OF THE NORTHERN BAJA 
PENINSULA WILL INCREASE TO AT LEAST 20 KT BY LATE TUE INTO EARLY 
WED AS THE RIDGE BUILDS FROM THE WEST...AND LOW PRES DEEPENS 
OVER THE SW UNITED STATES AND NW MEXICO. THE LARGE AREA OF NW 
SWELL WILL DECAY BELOW 8 FT BY THIS TIME...ALTHOUGH 8 TO 11 FT 
SEAS WILL PERSIST N OF 25N E OF 125W BY MIDWEEK DUE TO THE 
ENHANCED FLOW OFF THE COAST OF THE NORTHERN BAJA PENINSULA. 

THE GFS AND ECMWF HINT OF BRIEF PULSE OF FRESH WESTERLY FLOW 
INTO THE GULF OF CALIFORNIA ACROSS GAPS IN THE HILLY TERRAIN OF 
THE BAJA PENINSULA LATE TUE THROUGH WED. 

LOOKING AHEAD TO LATE IN THE WEEK...WAVE MODELS SUGGEST LONG 
PERIOD SW SWELL IN EXCESS OF 8 FT WILL PROPAGATE NORTHWARD 
ACROSS THE EQUATOR...REACHING AS FAR NORTH AS 15N AND WITHIN 200 
NM OF THE CENTRAL AMERICAN AND SOUTHERN MEXICAN COASTLINES BY 
LATE FRI. 

$$
STRIPLING