000
AXPZ20 KNHC 101607
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC WED DEC 10 2008

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 
1500 UTC.

...ITCZ...
ITCZ IS ALONG 07N78W TO 08N100W TO 10N112W TO 07N126W TO 09N134W 
TO 07N140W. NUMEROUS STRONG CONVECTION WITHIN 180 NM N AND 90 NM 
S OF AXIS BETWEEN 110W AND 117W.

...DISCUSSION...

A DEEP MID- TO UPPER-LEVEL TROUGH DIGGING INTO THE SOUTH CENTRAL 
U.S. AND NORTHERN MEXICO HAS DRIVEN A STRONG COLD FRONT DEEP 
INTO MEXICO...AS FAR WEST AS THE WESTERN MEXICAN COAST. A STRONG 
AND INCREASING PRESSURE GRADIENT ASSOCIATED WITH 1034 MB HIGH 
OVER NORTHERN MEXICO HAS LED TO AN EXTENDED PERIOD OF BRISK NW TO
N WINDS ACROSS THE SEA OF CORTEZ AS WELL AS WEST OF COASTAL BAJA 
CALIFORNIA. AS THE FRONT PUSHES WELL SOUTH INTO MEXICO AND 
ULTIMATELY EVEN PARTS OF CENTRAL AMERICA...RAPIDLY RISING 
PRESSURES BEHIND THE BOUNDARY WILL LED TO THE DEVELOPMENT OF 
GALE CONDITIONS DOWNWIND OF THE GULF OF TEHUANTEPEC LATER 
TONIGHT AND DOWNWIND OF THE GULF OF PAPAGAYO IN ABOUT 48 HOURS. 
SEAS COULD BUILD AS HIGH AS 10 TO 16 FT DOWNWIND OF THE GULF OF 
TEHUANTEPEC OVER THE NEXT FEW DAYS.

AFTER PERSISTENT AND NEARLY CONTINUOUS FRESH TO SOMETIMES STRONG 
NW TO N FLOW IN THE SEA OF CORTEZ....MARINE CONDITIONS HAVE 
ALREADY RESPONDED. A MID-MORNING QUIKSCAT PASS SUGGESTED WINDS 
OF 20 TO 25 KT OVER THIS AREA...AS WELL AS W OF THE WEST COAST 
OF THE BAJA PENINSULA. ALTHOUGH THE NOAA WAVEWATCH FAILS TO 
PRODUCE NO MORE THAN 6 TO 7 FT SEAS OVER THE GULF OF 
CALIFORNIA...THE STRENGTH AND DURATION OF THE WINDS WOULD 
INDICATE THE POSSIBILITY OF 8 FT SEAS IN ISOLATED SPOTS. AS THE 
SURFACE HIGH BUILDS IN FURTHER AND THE PRESSURE 
EQUALIZES...WINDS SHOULD BEGIN TO DIE DOWN LATER THIS AFTERNOON 
AND OVERNIGHT. AS A RESULT...EXPECT MARINE CONDITIONS 
SURROUNDING THIS AREA TO BEGIN IMPROVING BY THU.

ELSEWHERE...THE PRESSURE GRADIENT SOUTH OF AN ENHANCED LOW-LEVEL 
SUBTROPICAL RIDGE OVER THE NE PACIFIC IS PRODUCING A BROAD ZONE 
OF 20 TO 25 KT NE TO E TRADE WINDS GENERALLY S OF 28N AND W OF 
125W. SINCE THESE WINDS HAVE ALREADY BEEN BLOWING FOR A WHILE 
...SEAS HAVE ALREADY BUILT UP TO 8 TO 11 FT OVER A LARGE AREA IN
A MIXTURE OF E WIND WAVES AND NW SWELL.
 
CYCLONIC TURING IS NOTED ALONG 119W ASSOCIATED WITH A WAVE IN 
THE EASTERLIES...DRIFTING W ALONG THE ITCZ. STRONG UPPER-LEVEL 
DIVERGENCE OVER THIS FEATURE AHEAD OF A WELL-DEFINED MID- TO 
UPPER-LEVEL CYCLONE AND ASSOCIATED TROUGH ROUGHLY ALONG 128W HAS 
RESULTED IN PERIODIC BURSTS OF INTENSE CONVECTION OVER THE LAST 
24 HOURS....WITH ISOLATED CONVECTIVE CLOUD TOPS TO -80C. THIS 
WAVE IS EXPECTED TO REMAIN ACTIVE DURING THE NEXT 12 HOURS AS 
IT REMAINS UNDER ANTICYCLONIC FLOW ALOFT...WITH DEEPEST 
CONVECTION PERSISTING WITHIN 3 TO 8 DEGREES E OF THE WAVE. 
MORNING SCATTEROMETER PASSES SHOW VERY GOOD CONVERGENCE FROM THE 
WAVE AXIS EASTWARD TO 110W.    
 
$$

STRIPLING/KIMBERLAIN