000
AXPZ20 KNHC 172117
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC WED SEP 17 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 2000 UTC.

...TROPICAL WAVES...
TROPICAL WAVE ALONG 85W SOUTH OF 20N...PASSING THROUGH 
HONDURAS...NICARAGUA...AND COSTA RICA...MOVING WEST
10 TO 15 KT. STRONG SHOWERS AND THUNDERSTORMS IN CENTRAL 
NICARAGUA.

TROPICAL WAVE ALONG 95W SOUTH OF 18N MOVING WEST 10 KT.
ITCZ SHOWERS AND THUNDERSTORMS.

TROPICAL WAVE ALONG 117W SOUTH OF 18N MOVING WEST 15 KT.
ISOLATED MODERATE SHOWERS FROM 8N TO 14N BETWEEN 114W AND 
120W.

A SURFACE TROUGH IS ALONG 130W/131W FROM 10N TO 16N. ITCZ 
SHOWERS AND POSSIBLE THUNDERSTORMS ARE FROM 9N TO 13N
BETWEEN 126W AND 134W.

...ITCZ...
10N85W 09N100W 11N115W 10N127W TO 11N140W. SCATTERED MODERATE 
SHOWERS TO ISOLATED STRONG THUNDERSTORMS FROM 11N TO 15N BETWEEN 
94W AND 99W. SCATTERED MODERATE SHOWERS TO ISOLATED STRONG
THUNDERSTORMS WITHIN 60 NM NORTH AND 270 NM SOUTH OF ITCZ
EAST OF 101W. 

...DISCUSSION...
MIDDLE TO UPPER LEVEL TROUGH MOVING ACROSS THE FAR NORTHWESTERN
CORNER OF THE DISCUSSION AREA HAS FLATTENED THE RIDGE THAT HAS 
BEEN OVER THE AREA DURING THE LAST SEVERAL DAYS. THE TROUGH 
EXTENDS FROM 32N131W TO 26N138W. AN UPPER LEVEL RIDGE IS ALONG 
29N116W 25N130W BEYOND 22N140W. STRONG SUBSIDENCE WITH DRY 
STABLE CONDITIONS COVER THE AREA NORTH OF 24N108W 17N125W 
10N140W.

A MIDDLE TO UPPER LEVEL TROUGH EXTENDS FROM SOUTHWESTERN
NEW MEXICO...ACROSS NORTHERN MEXICO...TO 26N110W IN THE
GULF OF CALIFORNIA. 

A SURFACE RIDGE PASSES THROUGH 34N126W TO A 1021 MB HIGH 
PRESSURE CENTER NEAR 29N131W...BEYOND 25N140W. 
BROKEN TO OVERCAST STRATOCUMULUS CLOUDS COVER THE AREA
NORTH OF 20N WEST OF 110W.

$$
MT