000
AXPZ20 KNHC 291513
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC MON OCT 29 2007

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

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 1430 UTC.

...ITCZ....
AXIS ALONG 9N84W 7N95W 13N123W 11N140W. SCATTERED MODERATE 
ISOLATED STRONG CONVECTION FROM 12N TO 15N BETWEEN 123W AND 136W.

...DISCUSSION...

E OF 110W...MAIN ISSUE REMAINS GALE WARNING IN EFFECT FOR THE 
GULF OF TEHUANTEPEC THOUGH THE NEXT COUPLE OF DAYS. THIS IS THE 
RESULT SURFACE HIGH PRES 1033 MB BUILDING OVER N CENTRAL MEXICO 
AND AN ASSOCIATED TIGHT GRADIENT OVER THE GULF OF MEXICO. MODEL 
GUIDANCE HINTS THAT GALE CONDITIONS WILL INCREASE SLIGHTLY THIS 
EVENING...BUT REMAIN BELOW STORM FORCE...BEFORE GRADUALLY 
DIMINISHING BELOW GALE FORCE ON WED. QUIKSCAT DATA SHOW FRESH NE 
TO E WINDS RELATED TO THE TEHUANTEPEC WINDS EXTENDING N OF THE 
ITCZ AS FAR W AS 105W. A FEW SHIP REPORTS CONFIRM WW3 GUIDANCE 
INDICATING 8 TO 10 FT SWELL MAY BE ONGOING S OF TEHUANTEPEC AS 
FAR S AS 5N RELATED TO THE STRONG GAP WINDS. N UPPER TROUGH 
EXTENDS FROM CENTRAL TEXAS TO S OF BAJA NEAR 19N110W. NLY FLOW 
ALOFT BETWEEN THE TROUGH AND UPPER RIDGE TO THE W ARE BRINGING 
VERY DRY MID AND UPPER LEVEL AIR ACROSS THE WHOLE AIR. THIS IN 
TURN IS INHIBITING JUST ABOUT EVERYWHERE. ONLY SOME MODEST 
SHOWERS LEFTOVER FROM NOCTURNAL CONVECTION ARE NOTED ALONG THE 
COSTA RICAN COAST. 

W OF 110W...UPPER RIDGE IS CENTERED NEAR 21N118W. FURTHER W...AN 
UPPER TROUGH EXTENDS ALONG 140W N OF 16N. A CLUSTER OF MODERATE 
TO STRONG CONVECTION DESCRIBED ALONG THE ITCZ IS BEING ENHANCED 
BY DIVERGENCE ALOFT ON THE SOUTHERN EDGE OF THE UPPER RIDGE...AS 
WELL AS BEING FED BY CONVERGENCE ALONG THE ITCZ. THE RESULTING 
SURFACE TROUGH WILL LIKELY PROPAGATE SLOWLY W OVER THE NEXT 
COUPLE OF DAYS. FRESH TRADES WILL PERSISTS ON THE PERIPHERY OF 
HIGH PRES 1028 MB CENTERED NW OF THE AREA...WITH ASSOCIATED 
SWELL OF UP TO 12 FT TODAY...AND 11 FT TOMORROW....MAINLY N OF 
10N AND W OF 125W.

$$
CHRISTENSEN