000
AXPZ20 KNHC 220333
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC MON DEC 22 2008

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 
0300 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 07N77W 06N90W 07N105W 06N115W  
12N133W 09N140W. SCATTERED MODERATE CONVECTION IS FROM 10N TO 
13N BETWEEN 127W AND 133W.   

...DISCUSSION...
A REX BLOCK PATTERN IS WELL ESTABLISHED OVER MUCH OF THE 
DISCUSSION AREA WITH AN UPPER LOW SPINNING NEAR 20N137W...FLAT 
TROUGHING OVER NRN BAJA AND MUCH OF THE SW CONUS AND LARGE 
AMPLIFIED RIDGING JUST W OF THE AREA...INCLUDING OVER THE 
HAWAIIAN ISLANDS. INSTABILITY NEAR THE UPPER LOW AND LOW-LEVEL 
CONVERGENCE ALONG AN ASSOCIATED SFC TROUGH IS PRODUCING 
SCATTERED MODERATE CONVECTION FROM 14N-22N BETWEEN 129W-135W. 
SCATTERED MODERATE TO ISOLATED STRONG CONVECTION LIES IN AN 
UPPER DIFFLUENT ZONE E OF THE UPPER LOW FROM 15N-19N BETWEEN 
117W-124W. THIS STAGNANT PATTERN IS EXPECTED TO HOLD FOR A FEW 
MORE DAYS BEFORE SLOWLY BREAKING DOWN AS A SERIES OF SHORTWAVES 
HELP DEEPEN THE TROUGH OVER THE NE PORTION OF THE AREA. 

AT THE SFC...TIGHT PRES PATTERN BETWEEN A 1025 MB HIGH NEAR 
31N132W AND TROUGHING ASSOCIATED WITH THE UPPER LOW IS PRODUCING 
A SWATH OF 20-30 KT NE/E TRADES FROM 19N-25N. THESE STRONG WINDS 
COMBINED WITH RESIDUAL N SWELL IS ELEVATING SEAS ABOVE 8 FT OVER 
MUCH OF THE W PORTION OF THE ZONE. THE SFC FEATURES DISCUSSED 
WILL SHIFT W OVER THE NEXT COUPLE OF DAYS...AND CONSEQUENTLY THE 
AREA OF STRONG WINDS WILL FOLLOW. 

GAP WINDS...
SEVERAL OF THE GAPS ARE ACTIVE TONIGHT...THOUGH NONE ARE OF 
WARNING CRITERIA. A QSCAT PASS REVEALED NW 20-25 KT WINDS OVER 
MUCH OF THE GULF OF CALIFORNIA ENHANCED BY A BACK-DOOR TYPE COLD 
FRONT AND STRONG HIGH PRES OVER THE GREAT BASIN. WINDS WILL 
SLACKEN OVER THE NEXT 24 HOURS AS THE WEATHER FEATURES SHIFT E. 
HOWEVER...NW WINDS WILL INCREASE TUE DUE TO A COLD FRONT. A GULF 
OF PAPAGAYO...ALSO ENHANCED BY STRONG NE TRADES IN THE W 
CARIBBEAN IS FORECAST TO RETURN AND INCREASE TO 20-25 KT MON 
MORNING. N WINDS ARE ALSO FORECAST TO INCREASE TO 20-25 KT IN 
THE GULF OF TEHUANTEPEC MON MORNING AS A COLD FRONT SURGES S 
OVER THE BAY OF CAMPECHE. HOWEVER...CONDITIONS WILL IMPROVE MON 
NIGHT AND TUE AS THE FRONT IN THE GULF OF MEXICO LIFTS BACK N AS 
A WARM FRONT. 

$$
FORMOSA