000
AXPZ20 KNHC 211521
TWDEP 

TROPICAL WEATHER DISCUSSION                                    
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
1605 UTC SAT MAR 21 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC. 

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
            
ITCZ FROM 02N105W TO 05N115W TO 04N140W. NO SIGNIFICANT 
CONVECTION ALONG THE ITCZ AXIS.

...DISCUSSION... 

W OF 120W...A WEAK NEARLY ZONAL PATTERN ALOFT N OF 20N W OF 120W 
IS MAINTAINING GENERALLY TRANQUIL MARINE CONDITIONS OVER MUCH OF 
THE AREA. A 1023 MB HIGH PRES AREA REMAINS CENTERED NEAR 
29N128W...BLOCKING A WEAK AND DISSIPATING STATIONARY FRONT TO 
THE WEST REACHING FROM 30N134W TO 27N140W. FARTHER 
SOUTH...SCATTEROMETER SATELLITE DATA ALONG REPORTS FROM TOGA 
BUOYS AND THE NOAA SHIP RON BROWN INDICATE MODERATE TO FRESH 
TRADE WIND FLOW SOUTH OF THE SUBTROPICAL RIDGE. RECENT ALTIMETER 
SATELLITE DATA SHOW WAVE HEIGHTS BARELY REACHING TO 8 FT IN 
FRESH NE SWELL. THE RIDGE WILL TEMPORARILY WEAKEN AHEAD OF AN 
APPROACHING SHORT WAVE TROUGH NW OF THE AREA. THE RIDGE WILL 
BUILD IN THE WAKE OF THIS DISTURBANCE THROUGH LATE 
SUNDAY...ALLOWING TRADE WIND FLOW TO INCREASE SLIGHTLY FARTHER 
SOUTH FROM 08N TO 20N W OF 130W. MEANWHILE LONG PERIOD NW SWELL 
WILL MOVE INTO THE NW DISCUSSION AREA STARTING LATE 
SUNDAY...WITH 8 TO 11 FT SEAS.

E OF 120W...GENERALLY LIGHT TO MODERATE WINDS PERSIST WITH SEAS 
MOSTLY 3 TO 5 FT ACROSS THE REGION. AN UPPER TROUGH REACHING 
FROM 10N110W TO OVER THE GALAPAGOS ISLANDS WAS SUPPORTING MODEST 
CONVECTION WITHIN 300 NM N OF THE GALAPAGOS...BUT MUCH OF THIS 
HAS RECENTLY DISSIPATED. A SHARPER MORE ACTIVE UPPER TROUGH 
REACHING FROM AN UPPER DISTURBANCE IN N CENTRAL MEXICO TO 
10N115W IS SUPPORTING SHOWERS AND A FEW THUNDERSTORMS FROM 07N 
TO 12N BETWEEN 110W AND 115W. A BUILDING SUBTROPICAL RIDGE ON 
SUNDAY WILL ALLOW NORTHERLY WINDS TO INCREASE OFF THE COAST OF 
BAJA CALIFORNIA NORTE. ASSOCIATED SEAS WILL BUILD TO 8 TO 9 FT 
WITH FRESH NW SWELL REACHING AS FAR SOUTH AS 22N THROUGH TUESDAY 
OFF THE COAST OF THE BAJA CALIFORNIA PENINSULA. LOOKING 
AHEAD...ANOTHER BUILDING RIDGE OVER THE GULF OF MEXICO WILL 
SUPPORT FRESH TO STRONG GAP WINDS THROUGH THE GULF OF 
TEHUANTEPEC LATE MONDAY AND EARLY TUESDAY. LOOKING FURTHER 
AHEAD...VARIOUS WAVE MODELS ARE INDICATING LONG PERIOD SW SWELL 
CROSSING THE EQUATOR W OF THE GALAPAGOS ISLANDS ON 
TUESDAY...WITH WAVE HEIGHTS TO AT LEAST 7 FT REACHING THE 
MEXICAN AND CENTRAL AMERICAN COASTS BY LATE WEDNESDAY OR EARLY 
THURSDAY.
 
$$
CHRISTENSEN