000
AXPZ20 KNHC 140922
TWDEP 

TROPICAL WEATHER DISCUSSION    
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC SAT APR 14 2007

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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0300 UTC.

...ITCZ...
AXIS 5N77W 7N108W 4N120W 4N140W. ISOLATED MODERATE CONVECTION 
WITHIN 60 NM OF AXIS BETWEEN 117W AND 130W.

...DISCUSSION...
HIGHLY AMPLIFIED AND PROGRESSIVE UPPER PATTERN PERSISTS N OF 20N 
OVER THE EASTERN PACIFIC. UPPER RIDGING IS BUILDING INTO 
SOUTHERN CALIFORNIA ALONG 120W...AHEAD OF AN UPPER TROUGH 
DIGGING ALONG 130W. THE UPPER TROUGH IS SUPPORTING MOVEMENT OF A 
LATE SEASON COLD FRONT INTO THE NORTHERN DISCUSSION AREA N OF 
25N ALONG 135W. 1030 MB SURFACE HIGH PRES FOLLOWS THE WEAKENING 
FRONT TO THE NW OF THE DISCUSSION AREA NEAR 35N145W. THE SURFACE 
HIGH PRES WILL BUILD EWD TODAY...RESULTING IN A TIGHTENING 
GRADIENT AND INCREASING NW TO N WINDS OFF BAJA CALIFORNIA INTO 
SUN...AS WELL AS INCREASED TRADES S OF THE HIGH...GENERALLY N OF 
7N AND W OF 125W. THE RIDGING TO THEN WEAKENS SLIGHTLY ON MON 
DUE TO STRONG SHORT WAVE CROSSING THE NORTHERN 
PACIFIC...RESULTING IN A BRIEF PERIOD OF SLIGHTLY DIMINISHING 
AFOREMENTIONED WINDS LATE MON INTO TUE.

FURTHER S...CONVECTION ALONG THE ITCZ HAS DIMINISHED OVER 
THE PAST 24 HOURS...LIKELY THE RESULT OF WEAKER NLY SFC FLOW 
CONVERGING INTO THE AREA. UPPER DIFFLUENCE IS EVIDENT E OF 
110W...ON THE E SIDE OF A WEAK UPPER TROUGH GENERALLY ALONG 125W 
FROM 10N TO 20N. AS NLY FLOW INCREASES TODAY...MAY SEE 
RESURGENCE OF CONVECTION TODAY AND TONIGHT ALONG ITCZ UNDER THE 
DIFFLUENT AREA ALOFT.  

GAP WINDS...A STRONG LATE SEASON COLD FRONT WILL PUSH INTO THE 
GULF OF MEXICO THIS MORNING. HIGH PRES BUILDING IN THE WAKE OF 
THE FRONT WILL PROMOTE GAP WIND FLOW INTO GULF OF TEHUANTEPEC 
TONIGHT AND SUNDAY...REACHING GALE STRENGTH BY MIDDAY SUNDAY. 
THESE WINDS WILL DIMINISH STARTING LATE SUNDAY AS RETURN FLOW 
SETS UP OVER GULF OF MEXICO.

ENP WAVEWATCH MODEL CONTINUES TO INDICATE 5-6 FT 14S PERIOD WLY  
SWELL REACHING EXPOSED COASTLINE AREAS OF CENTRAL AMERICA AND 
SOUTHERN MEXICO BY THIS AFTERNOON.

$$
CHRISTENSEN