000
AXPZ20 KNHC 301546
TWDEP 

TROPICAL WEATHER DISCUSSION                                  
NWS NATIONAL HURRICANE CENTER MIAMI FL                      
1605 UTC SAT APR 30 2016

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.
  
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...        

A SURFACE TROUGH EXTENDS FROM 12N87W TO 09N83W TO 09N98W TO
06N110W TO 07N115W TO 07N119W. ANOTHER SURFACE TROUGH REACHES
FROM 02N122W TO 10N122W. THE ITCZ AXIS STRETCHES FROM 05N124W TO
04N140W. SCATTERED MODERATE CONVECTION IS PRESENT WITHIN 90 NM
EITHER SIDE OF A LINE FROM 06N80W TO 06N89W TO10N97W TO 07N110W
TO 09N120W.

...DISCUSSION...

HIGH PRES OF 1031 MB IS ANALYZED N OF THE DISCUSSION AREA AT
42N132W WITH A RIDGE EXTENDING SE TO NEAR 17N113E. LATEST ASCAT
IMAGERY CONFIRMS THE TIGHT PRESSURE GRADIENT BETWEEN THE RIDGE
AND LOW PRES OVER THE SW U.S. IS CAUSING FRESH TO STRONG NW
WINDS JUST W OF THE CALIFORNIA COAST. THESE WINDS HAVE GENERATED
10-11 FT NW SWELL WHICH CONTINUE TO PROPAGATE ACROSS THE NE
PORTION OF THE FORECAST AREA TOWARD THE W COAST OF THE BAJA
PENINSULA. THE PRESSURE GRADIENT HAS BEGUN TO RELAX. THIS WILL
ALLOW SEAS TO EVENTUALLY SUBSIDE TO 8 FT OR LESS WEST OF THE
CALIFORNIA AND THE BAJA COAST BY MIDDAY ON MONDAY. 

THE AREA OF FRESH TRADES BETWEEN 05N AND 25N W OF 120W HAS BEGUN
TO DIMINISH AS HIGH PRES LOCATED N OF AREA WEAKENS. SW SWELL
PROPAGATING ACROSS THE REGION THAT ORIGINATED IN THE SOUTHERN
HEMISPHERE CONTINUE TO DISPERSE. AS A RESULT...SEAS WILL
GRADUALLY SUBSIDE ACROSS THE WATERS W OF 110W DURING THE NEXT 48
HOURS. SEAS ARE FORECAST TO SUBSIDE TO LESS THAN 8 FT ACROSS
THE ENTIRE BASIN BY SUNRISE ON MONDAY. 

A SURFACE TROUGH EXTENDS SOUTHWARD FROM LOW PRESSURE OVER
ARIZONA INTO THE GULF OF CALIFORNIA. THE TIGHT GRADIENT BETWEEN
HIGH PRESSURE OFFSHORE AND THE LOW AND TROUGH IS EXPECTED TO
GENERATE S-SW WINDS OF 20-25 KT ACROSS THE FAR NORTHERN GULF OF
CALIFORNIA TODAY AND TONIGHT. THESE WINDS ARE FORECAST TO
DIMINISH AROUND SUNRISE ON SUNDAY AS THE TROUGH FILLS AND THE
PRESSURE GRADIENT SLACKENS.

A COLD FRONT IS FORECAST TO REACH THE FAR NW CORNER OF THE AREA
ON MON...THEN CONTINUE SE AND DISSIPATE BY THU. FRESH WINDS
BEHIND THE FRONT WILL BRING ANOTHER ROUND OF NW SWELL. EXPECT
SEAS BUILDING TO 8-9 FT IN THE WAKE OF THE FRONT ON MONDAY
NIGHT AND TUESDAY.
.

$$
MCELROY