000
AXPZ20 KNHC 162155
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC TUE SEP 16 2008

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

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2100 UTC.

...TROPICAL WAVES...

TROPICAL WAVE ALONG 89W N OF 04N INTO CENTRAL AMERICA IS MOVING 
W ABOUT 10 KT. THE WAVE IS RELATIVELY WEAK AND DISORGANIZED.

TROPICAL WAVE ALONG 110W FROM 04N TO 16N IS MOVING W ABOUT 10 
KT. THIS WAVE IS ALSO WEAK WITH MINIMAL CONVECTION ASSOCIATED 
WITH IT.

...ITCZ...

ITCZ AXIS IS CENTERED FROM 09N82W TO 08N92W TO 10N116W TO 
12N126W TO 09N140W. NUMEROUS MODERATE SCATTERED STRONG 
CONVECTION IS LOCATED WITHIN 300 NM OF AXIS BETWEEN 79W AND 85W.
SCATTERED MODERATE ISOLATED STRONG CONVECTION IS LOCATED WITHIN 
240 NM S OF AXIS BETWEEN 85W AND 91W. SCATTERED MODERATE 
CONVECTION IS LOCATED WITHIN 60 NM N AND 90 NM S OF AXIS W OF 
137W.

...DISCUSSION...

W OF 105W...
WATER VAPOR IMAGERY INDICATES STRONG SUBSIDENCE N OF A LINE FROM 
SOUTHERN BAJA CALIFORNIA TO 17N130W TO 12N140W. A MIDDLE/UPPER 
LEVEL RIDGE AXIS EXTENDS THROUGH 23N140W TO NEAR 25N125W WITH 
ANTICYCLONIC FLOW NOTED FROM 15N TO 28N W OF 125W. INCREASING SW 
FLOW ALOFT IN ADVANCE OF A MIDDLE/UPPER LEVEL TROUGH IS LOCATED 
OVER THE NW PART OF THE DISCUSSION AREA W OF A LINE FROM 32N133W 
TO 28N140W. A MIDDLE/UPPER LEVEL TROUGH AXIS IS LOCATED ALONG 
113W N OF 25N WITH CYCLONIC FLOW LOCATED N OF 25N E OF 120W INTO 
NW MEXICO. WESTERLY WINDS ALOFT ARE FORECAST OVER THE AREA N OF 
25N IN THE NEXT 24 TO 48 HOURS. FLOW ALOFT S OF THE SUBSIDENCE 
LINE NOTED ABOVE TO THE EQUATOR IS EASTERLY WITH SATELLITE CLOUD 
DRIFT WINDS INDICATING SPEEDS AS HIGH AS 40 TO 45 KT. AT THE 
SURFACE A WEAK TROUGH IS LOCATED FROM 14N129W TO 08N130W. A 
RIDGE EXTENDS FROM A 1021 MB HIGH NEAR 32N138W TO 22N120W. 
SOUTHWESTERLY SWELLS TO 10 FT ARE LOCATED S OF 10N BETWEEN 105W 
AND 120W. 

E OF 105W...
WINDS ALOFT OVER THE AREA E OF 105W ARE EASTERLY AND ARE 
STRONGEST S OF 05N TO THE EQUATOR BETWEEN 85W AND 100W AND 
MEASURE UP TO 50 KT. SOUTHWESTERLY SWELLS TO 10 FT ARE LOCATED S 
OF 10N BETWEEN 93W AND 105W. NORTH WINDS FROM 20 TO 25 KT ARE 
LOCATED OVER THE GULF OF TEHUANTEPEC AND WILL CONTINUE FOR THE 
NEXT 48 HOURS. 

$$
CAB