000
AXPZ20 KNHC 240315
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC FRI JUL 24 2009

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN
FROM THE EQUATOR TO 32N...EAST OF 140W. 

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0315 UTC.

...TROPICAL WAVES...
A TROPICAL WAVE HAS MOVED ACROSS THE WESTERN CARIBBEAN AT 20 KT 
TO ALONG 80W. ONLY A SMALL CLUSTER OF CONVECTION IS NOTED AT 
09N81W. 
  
A TROPICAL WAVE N OF 04N ALONG 94W HAS MOVED W AROUND 25 KT OVER 
THE PAST 48 HOURS. THE WAVE IS MOVING UNDER AN AREA OF UPPER 
LEVEL DIFFLUENCE ASSOCIATED WITH AN UPPER RIDGE THAT IS 
STATIONARY OVER THE TROPICAL PACIFIC E OF 103W. ISOLATED 
MODERATE AND STRONG CONVECTION IS FLARING ALONG THE WAVE AT 07N 
AND 12N. 
   
A TROPICAL WAVE FROM 04N TO 14N ALONG 105W HAS MOVED W AT ABOUT 
19 KT OVER THE PAST 24 HOURS. CONVECTION IS FLARING WITHIN 30 NM 
OF THE WAVE AXIS AT 10N...BUT OVERALL CONVECTION IS DIMINISHING 
AS THE WAVE ENTERS AN AREA THAT IS UNFAVORABLE FOR CONVECTION.

A TROPICAL WAVE IS ANALYZED FROM 05N TO 14N AROUND 129W BUT IS 
BECOMING DIFFICULT TO LOCATE. THIS WAVE IS MOVING THROUGH AN 
AREA OF SOUTHWESTERLY UPPER SHEAR THAT IS LIKELY STRETCHING 
CONVECTION WELL E OF THE SURFACE SIGNATURE.

...ITCZ...
THE AXIS IS NOTED ALONG POINTS FROM 07N77W TO 06N87W TO 
09N97W TO 07N116W TO 09N129W TO 08N140W. SCATTERED MODERATE 
ISOLATED STRONG CONVECTION IS OBSERVED WITHIN 150 NM EITHER SIDE 
OF A LINE FROM 05N84W TO 11N105W AND ALSO WITHIN 180 NM OF LINE 
FROM 15N120W TO 08N140W.  

...DISCUSSION...
AN UPPER LEVEL TROPICAL ANTICYCLONE IS CENTERED NEAR 09N136W 
WITH AN UPPER RIDGE EXTENDING E TO W OVER THE ITCZ BETWEEN 122W 
AND 142W. THE DEBRIS MOISTURE SEEMS TO REMAIN WITHIN THE AREA 
BOUNDED BY 06N TO 15N BETWEEN 118W AND 145W...BUT SOME OF THE 
DEBRIS CIRRUS HAS SPREAD N TO NEAR 17N138W.  

AN UPPER ANTICYCLONE IS CENTERED OVER EXTREME NORTHERN OLD 
MEXICO AT 31N109W WITH ITS ANTICYCLONIC ENVELOPE EXTENDING S 
OVER THE DISCUSSION AREA N OF 26N BETWEEN 103W AND 117W. ANOTHER 
UPPER ANTICYCLONE CENTERED OVER THE SW CARIBBEAN HAS A RIDGE 
EXTENDING SW ACROSS CENTRAL AMERICA TO A CREST AT 10N104W AND 
HAS BEEN ENHANCING CONVECTION OVER THE TROPICAL E PACIFIC E OF 
THIS CREST. SOME OF THE DEBRIS CIRRUS IS ADVECTED NE ACROSS 
CENTRAL AMERICA AND THE NW CARIBBEAN. SOME OF THE DEBRIS 
MOISTURE IS ADVECTED S BUT SEEMS TO EVAPORATE BEFORE IT REACHES 
THE EQUATOR.

A DEEP LAYERED CYCLONE IS CENTERED NEAR 32N144W WITH ITS 
CYCLONIC FLOW DOMINATING THE UPPER LEVELS N OF 20N W OF 130W 
WHERE UPPER DEBRIS MOISTURE IS ALSO NOTED. A BAND OF DRY UPPER 
AIR IS NOTED WITHIN 120 NM EITHER SIDE OF POINTS 14N134W TO 
20N124W TO 29N121W. ANOTHER UPPER TROUGH EXTENDS ACROSS THE 
SOUTHERN GULF OF MEXICO AND ACROSS OLD MEXICO ALONG 20N100W INTO 
AN UPPER CYCLONE CUTTING OFF NEAR 10N108W...WITH THE TROUGH 
CONTINUING S CROSSING THE EQUATOR AT 100W.  

GAP WINDS...NE TO E WINDS IN AND JUST DOWNSTREAM OF THE GULF OF 
PAPAGAYO WILL PULSE TO 20 KT OVER THE NEXT FEW DAYS.

LONG PERIOD SOUTHERLY SWELLS RESULTING IN MAX SEAS OF 8 TO 12 FT 
ARE CROSSING THE EQUATOR REACHING THE PACIFIC COAST OF CENTRAL 
AMERICA AND SHOULD REACH CENTRAL BAJA PENINSULA LATE FRI THEN 
BEGIN TO DIMINISH ON SAT.

$$
NELSON