000
AXPZ20 KNHC 232117
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC TUE DEC 23 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.

...ITCZ...
ITCZ IS ALONG 5N77W 9N105W 7N120W 9N130W 7N140W. SCATTERED 
MODERATE ISOLATED STRONG CONVECTION WITHIN 90 NM EITHER SIDE OF 
AXIS FROM 118W-122W AND WITHIN 60 NM EITHER SIDE OF AXIS FROM 
128W-137W.

...DISCUSSION...
THE LARGE MID/UPPER LEVEL CYCLONIC CIRCULATION HAS MOVED W OF 
THE DISCUSSION AREA NEAR 18N144W...HOWEVER UPPER LEVEL DIFFLUENT 
FLOW NE OF THE CIRCULATION IS ENHANCING AN AREA OF CONVECTIVE 
ACTIVITY FROM 17N-21N BETWEEN 137W-140W. UPPER LEVEL RIDGE WITH 
AXIS FROM 29N132W TO 9N117W. BROAD DEEP LAYER TROUGH IS N OF 27N 
BETWEEN 102W AND 117W. ASSOCIATED SURFACE COLD FRONT EXTENDS 
FROM SE ARIZONA ACROSS THE CENTRAL BAJA PENINSULA TO 26N123W. 
THERE ARE A FEW SHOWERS E OF THE FRONT ALONG THE ARIZONA/MEXICO
BORDER. 

AN UPPER LEVEL CYCLONIC CIRCULATION IS CENTERED NEAR 13N105W 
WITH TROUGH 8N108W. STRONG SUBSIDENCE WITH DRY STABLE AIR AT THE 
MIDDLE AND UPPER LEVELS OF THE ATMOSPHERE DOMINATES THE AREA E 
OF 110W. SKIES ACROSS THE AREA ARE MOSTLY CLEAR EXCEPT FOR A 
BAND OF LOW CLOUDS ALONG 10N AND S OF THE ITCZ.

A COUPLE OF SURFACE TROUGHS AREA ANALYZED ALONG THE ITCZ...THE 
FIRST FROM 18N 109W TO 8N110W. SCATTERED SHOWERS AND TSTMS ARE 
WITHIN 180 NM E OF THE TROUGH N OF 16N. THE SECOND TROUGH FROM
15N133W TO 9N114W. SCATTERED SHOWERS ARE WITHIN 60 NM EITHER 
SIDE OF THE TROUGH.

$$
DGS