000
AXPZ20 KNHC 132131
TWDEP 

TROPICAL WEATHER DISCUSSION                                    
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
2205 UTC MON APR 13 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1930 UTC. 
 
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...              

THE ITCZ AXIS WAS ANALYZED FROM 09N84W TO 03N89W TO 05N110W TO 
02N125W TO 06N131W TO 05N140W. SCATTERED MODERATE CONVECTION WAS 
WITHIN 270 NM SE OF THE AXIS E OF 92W. SCATTERED MODERATE 
CONVECTION WAS WITHIN 330 NM N AND 90 NM S OF THE AXIS W OF 
130W. A TROUGH LIES ALONG THE COAST OF COLOMBIA FROM 06N77W TO 
03N79W. SCATTERED MODERATE CONVECTION WAS WITHIN 150 NM NW OF 
THE TROUGH. 

...DISCUSSION... 

A SURFACE RIDGE EXTENDS FROM 1024 MB HIGH PRES NEAR 30N127W 
THROUGH 15N110W TO 12N94W. MOSTLY MODERATE TRADE WINDS LIE SW OF 
THE RIDGE AT THE MOMENT. THE RIDGE SHOULD GRADUALLY STRENGTHEN 
THROUGH THE END OF THE FORECAST PERIOD WED AFTERNOON AS HIGH 
PRESSURE MOVES IN BEHIND A COLD FRONT EXPECTED TO PUSH INTO THE 
WESTERN U.S. TONIGHT. TRADE WINDS SHOULD PICK UP TO A FRESH 
BREEZE OVER W WATERS TUE AS A RESULT...WITH WINDS EXPECTED TO 
REACH ADVISORY CRITERIA OVER THE AREA FROM 20N-23N W OF 132W TUE 
AFTERNOON THROUGH WED AFTERNOON.

N-NW WINDS ALONG THE CALIFORNIA COAST COUPLED WITH NW SWELL 
ASSOCIATED WITH THE AFOREMENTIONED COLD FRONT N OF THE AREA ARE 
GENERATING SEAS OVER 8 FT IN E WATERS N OF 30N THIS AFTERNOON. 8-
9 FT SEAS WILL GRADUALLY SPREAD S AND W ACROSS N WATERS THROUGH 
TUE. AT THE SAME TIME...THE PRESSURE GRADIENT WILL BUILD BETWEEN 
THE FRONT OVER THE INTERIOR WESTERN U.S. AND THE 1036 MB 
SUBTROPICAL HIGH NEAR 38N135W. WINDS TO GALE FORCE ARE EXPECTED 
N OF 31N...WITH N-NW WINDS TO ADVISORY CONDITIONS REACHING AS 
FAR S AS 29N TUE NIGHT THROUGH WED MORNING. SEAS WILL QUICKLY 
BUILD OVERNIGHT TUE NIGHT FROM 8-10 FT TO 10-14 FT WED MORNING N 
OF 29N BETWEEN 120W-125W. WINDS WILL DIMINISH BELOW ADVISORY 
CONDITIONS BY WED AFTERNOON AS THE COLD FRONT CONTINUES E AWAY 
FROM THE AREA. 
 
AN UPPER LEVEL LOW NEAR THE GALAPAGOS ISLANDS HAS A RIDGE AXIS 
TO ITS NE EXTENDING ACROSS COLOMBIA TO 05N77W TO 08N86W. 
CONVECTION IS BEING ENHANCED NEAR A SURFACE TROUGH ALONG THE 
COAST OF COLOMBIA AND ALONG THE EASTERN PORTION OF THE ITCZ AXIS 
AS A RESULT. MEANWHILE...AN ANTICYCLONE ALOFT NEAR 07N118W 
EXTENDS A RIDGE AXIS TO BEYOND 08N140W. THE DIVERGENCE ALOFT 
ASSOCIATED WITH THIS RIDGE IS ENHANCING CONVECTION ON THE W END 
OF THE ITCZ. THIS CONVECTION IS DESCRIBED IN THE SECTION ABOVE.

GAP WINDS...                                                     
GULF OF CALIFORNIA...THE COLD FRONT MOVING THROUGH THE INTERIOR 
WESTERN U.S. WILL MOVE INTO THE NORTHERN GULF OF CALIFORNIA WED 
MORNING. N-NW WINDS WILL PICK UP TO NEAR GALE FORCE N OF 29N BY 
WED AFTERNOON. 

$$
SCHAUER