000
AXPZ20 KNHC 251601
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC WED NOV 25 2009

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

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1545UTC.

...ITCZ...

AXIS ANALYZED FROM 08N78W TO 05N95W TO 08N113W TO 09N140W. 
SCATTERED MODERATE ISOLATED STRONG CONVECTION NOTED FROM 05N TO 
11N TO THE E OF 85W AND WITHIN 30 NM OF 07N89W AND ALSO WITHIN 
120 NM OF ITCZ AXIS BETWEEN 105W AND 140W.   


...DISCUSSION...

AN UPPER ANTICYCLONE AT 10N142W HAS A SHORTWAVE RIDGE EXTENDING 
N TO A CREST NEAR 35N140W. THE UPPER LEVELS ARE DRY N OF 15N W 
OF 125W. A TROPICAL UPPER ANTICYCLONE IS ESTIMATED AT 04N123W 
WITH A SHORTWAVE RIDGE EXTENDING NNE TO A CREST ALONG 30N NEAR 
110W. ABUNDANT UPPER MOISTURE IS NOTED UNDER THIS RIDGE... 
ROUGHLY FROM 15N TO 28N BETWEEN 123W AND 105W. BROAD UPPER 
RIDGING DOMINATES THE DEEP TROPICS S OF 15N TO THE E OF 90W AND 
IS ENHANCING THE ITCZ CONVECTION PREVIOUSLY DESCRIBED...WITH THE 
DEBRIS MOISTURE NOW SPREADING N OVER THE WESTERN CARIBBEAN. AN 
UPPER CYCLONE OVER CALIFORNIA HAS A TROUGH EXTENDING S THROUGH 
ANOTHER SMALL UPPER CYCLONE AT 26N121W WITH THE TROUGH 
CONTINUING SW TO NEAR 12N126W. A SECOND UPPER TROUGH IS SWINGING 
E ACROSS THE WESTERN GULF OF MEXICO RESULTING IN A LARGE AREA OF 
DRY UPPER AIR S OF 23N BETWEEN 103W AND 93W SUPPRESSING ITCZ 
CONVECTION.    

AT THE SURFACE...HIGH PRESSURE DOMINATES THE AREA W OF 105W WITH 
NE TRADES AT 20 TO 25 KT S OF THE RIDGE. STRONGER HIGH PRESSURE 
WILL PASS N OF THE AREA FRI INCREASING THE AREA OF NE TRADES.
SEAS TO 12 FT ARE CURRENTLY NOTED SW OF THE RIDGE WITH ANOTHER 
SET OF LONG PERIOD NW SWELLS EXPECTED TO MOVE INTO THE NW 
PORTION OF THE FORECAST AREA THU MORNING WITH SEAS BUILDING TO 
16 FT. NW SWELLS ARE COVERING THE ENTIRE AREA W OF 112W.

...GAP WINDS...
EASTERLY TRADES IN THE W CARIBBEAN WILL MAINTAIN SURGES TO 20 KT 
IN AND DOWNSTREAM OF THE GULF OF PAPAGAYO FOR THE NEXT FEW DAYS. 

STRONG HIGH PRESSURE OVER THE NW CONUS COMBINED WITH LOW 
PRESSURE W OF BAJA CALIFORNIA IS MAINTAINING A TIGHT PRESSURE 
GRADIENT RESULTING IN NORTHERLY WINDS AT 20 TO 25 KT IN THE 
NORTHERN GULF OF CALIFORNIA. THE GRADIENT WILL DECREASE OVER THE 
NEXT 24 TO 30 HOURS DIMINISHING THE WINDS BELOW 20 KT.

NORTHERLY WINDS SHOULD PICK UP TO 20 TO 25 KT THIS MORNING IN 
THE GULF OF TEHUANTEPEC AND FURTHER INCREASE TO A GALE AROUND 
SUNSET TODAY AND CONTINUE TO INCREASE TO A MINIMAL STORM EARLY 
FRI.

$$

NELSON