000
AXPZ20 KNHC 130903
TWDEP 

TROPICAL WEATHER DISCUSSION                  
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
1005 UTC SUN APR 13 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0830 UTC. 

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
 
THE MONSOON TROUGH EXTENDS FROM 09N84W TO 07N92W. THE ITCZ 
EXTENDS FROM 07N92W TO 05N100W TO 07N115W TO 01N135W TO 00N140W. 
SCATTERED MODERATE WITHIN 60 NM EITHER SIDE OF AXIS BETWEEN 85W 
AND 90W...AND BETWEEN 95W AND 105W. SCATTERED MODERATE WITHIN 90 
NM N OF AXIS BETWEEN 105W AND 120W. 

...DISCUSSION...                                                

A MID/UPPER LEVEL RIDGE N OF 30N IS MOVING EAST THROUGH 
135W...AHEAD OF A SHARP UPPER TROUGH N OF 15N ALONG ROUGHLY 
150W. A WEAK SURFACE RIDGE EXTENDS FROM 30N135W TO 
17N110W...MAINTAINING MODERATE TO OCCASIONALLY FRESH TRADES FROM 
06N TO 10N W OF 130W. A PAIR OF ALTIMETER PASSES OVER THE 
PREVIOUS SEVERAL HOURS INDICATES SEAS ARE APPROACHING 8 FT IN 
THIS AREA...LIKELY DUE IN PART TO SE SWELL.

THE UPPER TROUGH WILL CUT OFF INTO AN UPPER LOW CENTERED NE OF 
HAWAII NEAR 25N145W EARLY IN THE WEEK...TO THE SOUTH OF STRONG 
RIDGING BUILDING ACROSS THE NE PACIFIC. GLOBAL MODELS INDICATE A 
WEAK SURFACE TROUGH WILL FORM ALONG 145W FROM 15N TO 
25N...ASSOCIATED WITH THE UPPER LOW. THE RESULTING TIGHTENING 
GRADIENT WILL ALLOW TRADE WINDS TO INCREASE S OF 15N W OF 130W. 
THE FORECAST FOR LATE MON INTO TUE IS A LITTLE ABOVE GFS 
GUIDANCE...INDICATING THE POTENTIAL FOR 20 TO 25 KT IN THIS AREA 
WITH SEAS TO 9 FT. IN ADDITION...UPPER FORCING ON THE SE SIDE OF 
THE UPPER LOW WILL ENHANCE SCATTERED SHOWERS AND THUNDERSTORMS 
ALONG AND N OF THE ITCZ FROM 05N TO 15N W OF 130W LATE MON 
THROUGH TUE. 

FARTHER WEST...A WEAKENING LOW AMPLITUDE UPPER ANTICYCLONE IS 
CENTERED NEAR 17N110W...N OF AN UPPER CYCLONE IN THE DEEP 
TROPICS NEAR 05N115W. DIVERGENT WESTERLY FLOW ALOFT WEST OF 
THESE FEATURES IS INTERACTING WITH MODEST TRADE WIND CONVERGENCE 
TO SUPPORT SCATTERED MODERATE CONVECTION NORTH OF THE ITCZ 
BETWEEN 105W AND 120W. DIVERGENCE BETWEEN THE TWO UPPER FEATURES 
IS ALSO SUPPORTING SCATTERED MODERATE CONVECTION ALONG THE ITCZ 
BETWEEN 95W AND 105W.  

GULF OF CALIFORNIA...HIGH PRES BUILDING OVER THE GREAT BASIN 
WILL ALLOW STRONG NW WINDS TO FUNNEL INTO THE NORTHERN GULF OF 
CALIFORNIA ON MONDAY...BEFORE TAPERING OFF INTO TUESDAY AS THE 
HIGH PRES SHIFTS EAST.

GULF OF TEHUANTEPEC...LOOKING AHEAD...WINDS OVER THE GULF OF 
TEHUANTEPEC WILL REMAIN FAIRLY LIGHT THROUGH AT LEAST TUESDAY. A 
COLD FRONT IS EXPECTED TO MOVE OFF THE COAST OF TEXAS INTO THE 
GULF OF MEXICO MON NIGHT. THE FRONT WILL REACH THE BAY OF 
CAMPECHE TUE WITH WINDS INCREASING OVER THE GULF OF TEHUANTEPEC 
TUE AFTERNOON. WINDS ASSOCIATED WITH THIS GAP WIND EVENT MAY 
REACH GALE FORCE TUE NIGHT.  

$$ 
CHRISTENSEN