000
AXPZ20 KNHC 300333
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC WED DEC 30 2009

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 
0315 UTC.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE IS CENTERED ALONG 4N77W 4N95W 
5N110W 5N122W 6N140W. SCATTERED MODERATE CONVECTION IS WITHIN 
120 NM S OF THE AXIS BETWEEN 121W-123W...AND WITHIN 30 NM S OF
THE AXIS BETWEEN 116W-119W.

...DISCUSSION...

A MID/UPPER LEVEL TROUGH EXTENDS FROM THE WESTERN U.S. SW TO 
ACROSS NORTHERN BAJA CALIFORNIA TO 24N120W TO 22N130W TO 
17N136W. TO ITS SW VERY BROAD UPPER RIDGING COVERS THE AREA S OF 
18N AND W OF 110W. A RATHER SUBTLE SHORTWAVE TROUGH IS TO THE SE
THE MID/UPPER UPPER TROUGH EXTENDING FROM 20N109W TO 13N104W S TO
8N102W SW TO NEAR 2N103W. JUST ABOUT THE ENTIRE AREA BETWEEN THE 
MID/UPPER LEVEL AND RIDGE IS UNDER PRETTY FAST ZONAL FLOW WITH 
SATELLITE WATER VAPOR INDICATING MODERATE SUBSIDENCE AND 
ASSOCIATED STABLE ATMOSPHERIC CONDITIONS NOTED AS PATCHES OF 
BROKEN STRATOCUMULUS CLOUDS MOVING SSW TO N OF 13N. UPPER LEVEL 
MOISTURE IS SPILLING UP AND AROUND A LARGE MID/UPPER LEVEL RIDGE 
W OF THE AREA SOUTHEASTWARD INTO THE FAR NORTHERN BOUNDARY OF 
THE AREA BEHIND THE MID/UPPER LEVEL TROUGH. STRONG JEST STREAM 
BRANCH JUST N OF THE ITCZ IS ADVECTING UPPER LEVEL ITCZ MOISTURE 
NE ACROSS SOUTHERN MEXICO AND INTO TEXAS. AN UPPER ANTICYCLONE 
CENTERED OVER THE CENTRAL CARIBBEAN SEA EXTENDS A RIDGE WNW 
ACROSS CENTRAL AMERICA INCLUDING THE FAR EASTERN PACIFIC TO
E OF 95W. 

AT THE SURFACE...A HIGH CENTER OF 1026 MB IS LOCATED NEAR 
28N130W WITH A RIDGE TO 24N118W TO NEAR 21N108. RELATIVELY LOWER 
PRES TO THE S IN COMBINATION WITH THE HIGH TO THE N CONTINUES TO 
RESULT IN A LARGE SWATH OF FRESH TO STRONG TRADE WINDS OVER AN 
AREA S OF 18N W OF 130W AND FROM 7N TO 18N BETWEEN 116W AND 
130W. THE MAIN STORY THERE WILL BE LARGE SWELLS CONSISTING OF
NW AND NE COMPONENTS RESULTING IN 10 TO 13 FT. BY 36 AND 48 HRS
...THESE SWELLS SHOULD BE PRIMARILY FROM THE NW IN DIRECTION
WITH SEAS SLIGHTLY LOWER.

THE HIGH CENTER IS FORECAST TO REMAIN ABOUT STATIONARY
OVER THE NEXT 24 HRS AS A COLD FRONT MAKES HEADWAY TOWARDS THE 
FAR NW CORNER OF THE AREA. EXPECT THE AREA OF TRADES TO EXPAND
SOME EASTWARD THROUGH THE NEXT 48 HRS AS THE HIGH BEGINS TO 
SHIFT E. IN ADDITION NW WINDS OF 20 TO 25 KT ARE EXPECTED TO 
INCREASE THROUGH MUCH OF THE GULF OF CALIFORNIA AS WELL DUE TO 
AN INCREASING PRES GRADIENT BETWEEN THE HIGH AND LOWER PRES 
THROUGH THE GULF AND FAR OVER NW MEXICO. BY 48 HRS...THESE
WINDS SHOULD BE CONFINED TO THE SOUTHERN PORTION OF THE GULF.

WITH RESPECT TO ABOVE MENTIONED COLD FRONT...SW WINDS ARE 
FORECAST TO INCREASE OVER THE NW PORTION OF THE AREA BEGINNING 
WED MORNING WITH A NW SWELL TRAIN WITH A PERIOD OF ABOUT 
12-13 SECONDS PRODUCING SEAS OF 9 TO 13 FT EXPECTED TO PROPAGATE 
SE THROUGH THAT AREA INTO THE NEXT 48 HRS.

GAP WINDS...
GULF OF TEHUANTEPEC...N TO NE WINDS OF 20 TO 30 KT ARE 
FORECAST TO DIMINISH TO 20 KT BY WED NIGHT...AND TO LESS THAN 20 
KT BY THU EVENING WITH SEAS SUBSIDING TO LESS THAN 8 FT ALSO BY 
THU EVENING.

GULF OF PAPAGAYO... A WINDSAT PASS FROM AROUND 2330 UTC THIS 
EVENING SHOWED NE TO E WINDS OF 20 TO 25 KT FROM 9N TO 11N E OF 
88W. THIS AREA OF WINDS IS FORECAST TO SPREAD SLIGHTLY WESTWARD
DURING THE NEXT 24 HRS...THEN DIMINISH A LITTLE BY 48 HRS BUT
SHOULD AGAIN INCREASE AFTERWORDS.

FOR ADDITIONAL INFORMATION PLEASE VISIT 
HTTP://WWW.HURRICANES.GOV/MARINE
  
$$
AGUIRRE