000
AXPZ20 KNHC 041543
TWDEP 

TROPICAL WEATHER DISCUSSION                                    
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
1605 UTC FRI APR 04 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1515 UTC.                           

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

MONSOON TROUGH FROM 08N83W TO 06N90W. ITCZ AXIS FROM 06N90W TO 
05N105W...THEN IS DISCONTINUOUS FROM 02N105W TO 04N118W...AND 
AGAIN FROM 04N125W TO 04N135W. SCATTERED MODERATE CONVECTION IS 
NOTED WITHIN 90 NM SOUTH OF MONSOON TROUGH BETWEEN 82W AND 87W. 
 
...DISCUSSION...                                                

NORTH OF 20N...SHIP OBSERVATIONS AND SCATTEROMETER DATA OVER THE 
PAST SEVERAL HOURS OFF THE PACIFIC COAST OF THE BAJA PENINSULA 
INDICATED THAT WINDS HAVE DIMINISHED SLIGHTLY SINCE YESTERDAY 
AHEAD OF A WEAKENING DEEP LAYER SOUTHERN STREAM TROUGH MOVING 
EASTWARD THROUGH 125W. THE ASSOCIATED WEAKENING COLD FRONT 
REACHES FROM 30N125W TO 27N140W. THIS IS BREAKING UP THE 
SUBTROPICAL RIDGE RUNNING EAST TO WEST ALONG ROUGHLY 26N. WINDS 
ARE GENERALLY NW AT 15 TO 20 KT...ALTHOUGH LOCAL FUNNELING 
EFFECTS WILL ALLOW WINDS TO 25 KT ESPECIALLY OFF PUNTA EUGENIA. 
AN ALTIMETER PASS ALONG 120W FROM LAST NIGHT SHOWED SEAS TO 9 
FT...MATCHING WAVEWATCH III GUIDANCE SHOWING PERSISTENT LONG 
PERIOD NW SWELL OVER MUCH OF THE AREA N OF 20N W OF 120W. THE 
FRONT WILL DISSIPATE TONIGHT THROUGH SATURDAY AS IT DRIFTS INTO 
THE NORTHERN BAJA PENINSULA. STRONGER RIDGING BUILDING BEHIND 
THE FRONT WILL ALLOW WINDS TO INCREASE AGAIN OFF THE BAJA COAST 
OVERNIGHT AS 20 TO 25 KT NW WINDS COVER THE AREA WEST OF THE 
PENINSULA TO 125W. COMBINED SEAS WILL REACH 8 TO 10 FT IN THIS 
AREA BY LATE SAT. GLOBAL MODELS SUGGEST THE UPPER TROUGH WILL 
AMPLIFY ACROSS THE ROCKIES THIS WEEKEND...WITH ASSOCIATED 
SURFACE LOW PRES DEEPENING OVER N CENTRAL MEXICO. WHILE THE 
WINDS OFF THE WESTERN COAST OF BAJA WILL DIMINISH STARTING 
SUNDAY...FRESH TO POSSIBLY STRONG NW WINDS MAY SET UP OVER THE 
SOUTHERN CALIFORNIA SUNDAY INTO MONDAY. ELSEWHERE N OF 20N THE 
HIGH PRES NORTH OF THE AREA WILL MAINTAIN LIGHT TO MODERATE 
EASTERLY WINDS TO PERSIST INTO EARLY NEXT WEEK. SEAS WILL REMAIN 
JUST AT OR BELOW 8 FT IN LINGERING NW SWELL.

SOUTH OF 20N...SCATTEROMETER DATA OVER THE PAST SEVERAL HOURS 
INDICATES 20 TO 25 KT WINDS OVER A BROAD AREA FROM 06N TO 20N 
GENERALLY WEST OF 120W. THIS IS DUE TO A TIGHT PRES GRADIENT 
SOUTH OF 1026 MB HIGH PRES CENTERED NEAR 34N140W. SEAS ARE 
ESTIMATED TO RANGE FROM 8 TO 11 FT IN A MIX OF LONG PERIOD NW 
SWELL WITH SHORTER PERIOD NE SWELL. WEAK SURFACE TROUGHS ARE 
NOTED ALONG THE ITCZ NEAR 125W TO 135W. CLUSTERS OF SHOWERS AND 
THUNDERSTORMS ARE NOTED NEAR 10N117W...LIKELY DUE TO UPPER 
FORCING RELATED TO THE RIGHT REAR ENTRANCE REGION OF THE 
SOUTHERN STREAM JET. ELSEWHERE DESPITE DECENT SPEED CONVERGENCE 
IN THE LOWER LEVELS...DIVERGENCE IS LIMITED ALOFT AND CONVECTION 
REMAINS LIMITED. THE STRONG TRADE WINDS WILL GRADUALLY DIMINISH 
LATE SATURDAY THROUGH EARLY NEXT WEEK AS THE RIDGE TO THE NORTH 
WEAKENS. 
 
FARTHER EAST...DIVERGENCE ALOFT AT THE BASE OF AN UPPER TROUGH 
OVER COSTA RICA IS SUPPORTING WEAK CONVECTION NEAR 06N87W. GAP 
FLOW THROUGH THE GULF OF PAPAGAYO AND PANAMA REMAINS LIMITED FOR 
NOW. 

THE BIG ISSUE COMING UP BY MID WEEK WILL BE THE POSSIBILITY OF  
STRONG GALE OR EVEN STORM FORCE WINDS THROUGH THE GULF OF 
TEHUANTEPEC AS A STRONG COLD FRONT MOVES ACROSS THE GULF OF 
MEXICO. GLOBAL MODELS ARE IN GOOD AGREEMENT WITH GOOD RUN TO RUN 
CONSISTENCY SHOWING AT LEAST A GALE BY TUE NIGHT...WITH THE GFS 
AS USUAL THE STRONGEST MODEL SHOWING STRONG GALE TO MINIMAL  
STORM FORCE WINDS. 

$$
CHRISTENSEN