000
AXPZ20 KNHC 012142
TWDEP 

TROPICAL WEATHER DISCUSSION                                      
NWS NATIONAL HURRICANE CENTER MIAMI FL                           
2205 UTC SAT JUN 01 2013

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 
2030 UTC.

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

MONSOON TROUGH EXTENDS FROM NW COLOMBIA WWD ACROSS PANAMA AND  
COSTA RICA TO GUATEMALA WHERE IT BECOMES ILL DEFINED...THEN 
BEGINS AGAIN NEAR 15N102W TO 10N108W TO 12N116W TO 
10N120W...WHERE IT TRANSITIONS TO ITCZ AND CONTINUES TO 10N130W 
TO 07N140W. SCATTERED MODERATE CONVECTION IS ALONG THE COAST OF 
COSTA RICA FROM 7N TO 11N BETWEEN 83W AND 88W. SCATTERED 
MODERATE TO ISOLATED STRONG CONVECTION IS FROM 10N TO 14N 
BETWEEN 98W AND 107W. 

...DISCUSSION... 

STRONG NW WINDS PERSIST OFF THE COAST OF CALIFORNIA BETWEEN A 
1032 MB HIGH PRES NEAR 36N141W AND A STALLED FRONTAL TROUGH 
ALONG THE SIERRA NEVADA RANGE. SCATTEROMETER WINDS SHOWED NW TO 
N WINDS 20-25 KT SPILLING SOUTHWARD INTO N PORTIONS OF THE 
DISCUSSION AREA...LOCATED N OF 27.5N AND BETWEEN 121W AND 
129W...THEN TURNED ANTICYCLONICALLY AND DIMINISHED TO AROUND 20 
KT...EXTENDING SW TO BEYOND 18N140W. BUOYS OFFSHORE OF SOUTHERN 
CALIFORNIA SHOWED WAVE HEIGHTS A FEW FEET HIGHER THAN GLOBAL 
MODEL PREDICTIONS...WITH SEAS 8 TO 11 FT SPREADING S INTO THE 
LOCAL WATERS N OF 26N BETWEEN 122W AND 130W. GLOBAL MODELS ARE 
IN GOOD AGREEMENT SHOWING THE RIDGE BUILDING ALONG 140W OVER THE 
NEXT 24 TO 48 HOURS AS TROUGHING DEEPENS ACROSS THE WESTERN 
UNITED STATES AND EASTERN PACIFIC E OF 120W N OF 20N. THE 
STRENGTHENING RIDGE WILL ALLOW NE WINDS TO INCREASE SLIGHTLY 
THIS EVENING INTO MON N OF 20N W OF 120W WITH BUILDING SEAS. 
LOOKING AHEAD...THE RIDGE IS FORECAST TO WEAKEN TUE INTO MID 
WEEK AS THE SUPPORTING MID/UPPER TROUGH SHARPENS FROM SOUTHERN 
CALIFORNIA TO 19N140W...ALLOWING SURFACE WINDS TO DIMINISH. AS 
STATED ABOVE...FARTHER SOUTH...THE ATMOSPHERE REMAINS FAIRLY DRY 
AND STABLE...INHIBITING ANY MAJOR CONVECTION.

SOUTH OF 22N AND E OF 120W...MONSOONAL FLOW IS WELL 
ESTABLISHED...WITH BROAD CYCLONIC LOW LEVEL FLOW EXTENDING 
ACROSS SOUTHERN MEXICO AND CENTRAL AMERICA AND INTO THE FAR W 
AND SW CARIBBEAN AS WELL AS THE SOUTHERN GULF OF MEXICO. LIGHT 
TO MODERATE SWLY WINDS OCCURRING S OF THE MONSOON TROUGH ARE 
AIDING IN PRODUCING BROAD LOW LEVEL CONVERGENCE OF WINDS ACROSS 
CENTRAL AMERICA...LEADING TO VERY ACTIVE SHOWERS AND 
THUNDERSTORMS THERE. THIS VERY WET AND UNSTABLE PATTERN WILL 
CONTINUE INTO MONDAY ACROSS CENTRAL AMERICA AND FAR SE MEXICO 
INTO MONDAY...WITH SHOWERS AND THUNDERSTORMS ALONG POSSIBLE 
ALONG THE PACIFIC COASTS AND COASTAL ZONES.  
 
WITH LIGHT WINDS ACROSS THE REGION E OF 110W...SEAS ARE BEING 
DOMINATED BY LONG PERIOD SOUTHERN HEMISPHERE SW SWELL THAT WILL 
PREVAIL INTO EARLY NEXT WEEK. A VERY STRONG AND LARGE SW SWELL 
EVENT IS EXPECTED TO AFFECT THE REGIONAL WATERS AND COASTAL 
ZONES FROM BAJA CALIFORNIA TO COLOMBIA...BEGINNING MONDAY TO 
TUESDAY OF NEXT WEEK...AS VERY LONG PERIOD SW SWELL GENERATED 
ACROSS THE SOUTH CENTRAL PACIFIC MOVE INTO THE REGIONAL WATERS. 
SWELL WITH WAVE PERIODS OF 21 TO 24 SECONDS WILL INITIALLY 
ARRIVE MONDAY THROUGH TUESDAY...AND BUILD IN HEIGHT THROUGH MID 
WEEK. THIS SWELL EVENT WILL PRODUCE VERY STRONG AND DANGEROUS 
CONDITIONS IN THE SURF ZONE NEXT WEEK ALONG EXPOSED REEFS AND 
COASTLINES. 
 
$$ 
SS/MRF