000
AXPZ20 KNHC 250954
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC TUE NOV 25 2008

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

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0945 UTC.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 07N78W TO 
07N94W TO 11N126W TO 07N140W. SCATTERED MODERATE ISOLATED STRONG 
CONVECTION IS NOTED N OF 06N TO THE E OF 82W AND ALSO WITHIN 30 
NM EITHER SIDE OF A LINE FROM 08N96W TO 07N108W AND ALSO WITHIN 
180 NM OF 08N117W.

...DISCUSSION...

A DEEP LAYERED CYCLONE IS AT 30N131W WITH A MID TO UPPER TROUGH 
EXTENDING SE TO A BASE NEAR 22N122W AND SWINGING NE WITH TIME. 
SOME UPPER MOISTURE IS INDICATED N OF 27N W OF 125W BUT A DRY 
SLOT IS ALSO NOTED WITHIN 150 NM OF LINE 28N121W TO 22N128W TO 
22N140W. AN UPPER TROUGH EXTENDS ALONG 30N90W TO 20N93W INTO AN 
UPPER CYCLONE AT 10N105W. DRY UPPER AIR IS INDICATED N OF 08N 
BETWEEN 109W AND 86W.

A SHORTWAVE RIDGE HAS DEVELOPED BETWEEN THESE UPPER TROUGHS. A 
MOISTURE PLUME ORIGINATING FROM CENTRAL PACIFIC ITCZ CONVECTION 
NEAR 165W...IS ADVECTED E NE ENTERING THE DISCUSSION AREA WITHIN 
240 NM EITHER SIDE OF LINE 11N140W TO 14N122W...WHERE ADDITIONAL 
MOISTURE FROM ITCZ CONVECTION BETWEEN 110W AND 125W IS SPREADING 
N UNDER THE RIDGE. AT THE LOW LEVELS...WEAK LOW PRES HAS FORMED 
AT 21N123W 1012 MB WITH TROUGH S TO 10N127W. SCATTERED MODERATE 
ISOLATED STRONG CONVECTION IS NOTED WITHIN 30 NM OF LINE 23N116W 
TO 20N122W. THE RESULTANT DEBRIS MOISTURE FROM THIS CONVECTION 
ENFORCES THE TWO PLUMES MENTIONED ABOVE...WITH A LARGE TROPICAL 
PLUME STREAMING N BETWEEN 110W AND 120W OVER THE SW CONUS.     

AN UPPER ANTICYCLONE OVER COLOMBIA HAS A RIDGE EXTENDING W NW TO 
NEAR THE YUCATAN PENINSULA. BROAD LOW PRESSURE OVER THE SW 
CARIBBEAN PERSISTS WITH CONVECTION ENHANCED FROM 07N TO 17N 
BETWEEN 77W AND 86W...BASICALLY UNDER THE UPPER RIDGE. MOST OF 
THE DEBRIS MOISTURE IS ADVECTED E ACROSS THE CENTRAL CARIBBEAN. 

GAP WINDS...NORTHERLY WINDS IN AND DOWNSTREAM OF THE GULF OF  
TEHUANTEPEC ARE CURRENTLY AT 20 TO 25 KT WITH SEAS TO AROUND 11 
FT. HIGH PRES IN THE WAKE OF A COLD FRONT OVER THE GULF OF 
MEXICO IS EXPECTED TO SURGE INTO THE GULF OF TEHUANTEPEC BY MID 
MORNING WITH N WINDS INCREASING TO MINIMAL GALE AND CONTINUING 
TILL EARLY TONIGHT. NE WINDS ARE AT 20 TO 25 KT IN THE GULF OF 
PAPAGAYO AND EXPECTED TO PULSE TO 25 KT THROUGH 48 HOURS. BROAD 
LOW PRESSURE OVER THE SW CARIBBEAN WILL OCCASIONALLY DRIVE N 
WINDS ACROSS CENTRAL AMERICA INTO THE PAC WATERS ALONG THE COAST 
OF COSTA RICA AND WESTERN PANAMA.

$$
NELSON