000
AXPZ20 KNHC 122208
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC WED JAN 12 2011

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

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2100 UTC.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE AXIS IS CENTERED ALONG 07N78W 
TO 04N88W TO 07N110W TO 08N140W. SCATTERED MODERATE CONVECTION 
IS FROM 07N TO 12N W OF 134W.

...DISCUSSION...

A SURFACE RIDGE ANCHORED ON A 1027 MB HIGH CENTERED NEAR 32N124W 
CONTINUES TO DOMINATES THE REGION N OF 15N. AN AREA OF FRESH 
TRADES CAN BE FOUND ON THE SOUTHERN PERIPHERY OF THE RIDGE FROM 
GENERALLY 09N TO 20N W OF 115W. THIS WEATHER PATTERN IS EXPECTED 
TO PERSIST THROUGH THE PERIOD AND INTO THE WEEKEND AS THE HIGH 
PRESSURE CENTER REMAINS NEARLY STATIONARY ALONG THE NORTH- 
CENTRAL DISCUSSION BORDER. THE GULF OF CALIFORNIA ALSO HAS NW 
WINDS OF 20 TO 25 KT OCCURRING N OF 23N DUE TO A TIGHT PRESSURE 
GRADIENT OVER WESTERN MEXICO...THE GULF OF CALIFORNIA...AND THE 
BAJA. LITTLE CHANGE IS EXPECTED OVER THE NEXT COUPLE OF DAYS AS 
STRONG SURFACE TROUGHING REMAINS OVER THE GULF BETWEEN THE E 
PACIFIC RIDGING AND STRONG RIDGING OVER EASTERN MEXICO AND THE 
WESTERN GULF OF MEXICO. SOUTHERLY WINDS OF 20 KT ARE EXPECTED 
ACROSS THE FAR NW CORNER OF THE DISCUSSION AREA LOCATED ON THE 
WESTERN PERIPHERY OF THE SURFACE RIDGE...AHEAD OF A COLD FRONT 
APPROACHING THE CORNER OF THE AREA NEAR 30N140W. SEAS ARE 
EXPECTED TO BUILD TO 13 FT IN NW SWELL...THEN SUBSIDE GENERALLY 
BELOW 12 FT BY LATE FRIDAY.

ELSEWHERE IN THE AREA...LONG PERIOD NW SWELL CONTINUES TO 
PROPAGATE SE ACROSS THE EAST PACIFIC. PERIOD OF 16 TO 18 SECONDS 
ARE NOTED AT THE LEADING EDGE OF THE SWELL TRAIN WHICH HAS 
REACHED THE COASTS OF SW COLOMBIA AND WESTERN ECUADOR. A NEW 
SWELL TRAIN FROM THE NW HAS ENTERED THE NW PORTION OF THE AREA 
AND WILL TRAVERSE THE FORECAST WATERS W OF 118W THROUGH LATE 
FRIDAY...THEN MERGE WITH CROSS EQUATORIAL SW SWELL NEAR 110W 
THEREAFTER. WIND WAVES GENERATED BY THE GAP WIND EVENTS OF 
TEHUANTEPEC AND PAPAGAYO WILL ALSO MERGE AND MIX WITH THE LONGER 
PERIOD NW SWELL TO CREATE AN AREA OF CONFUSED SEAS BY EARLY 
FRIDAY THAT LASTS THROUGH THE WEEKEND.    

GAP WINDS...
STRONG NORTHERLY FLOW CONTINUES ACROSS THE SOUTHWESTERN GULF OF 
MEXICO AIDING IN STORM FORCE CONDITIONS THROUGH THE ISTHMUS AND 
INTO THE GULF OF TEHUANTEPEC. AN EARLIER ASCAT PASS THIS MORNING 
AROUND 12/1538 UTC INDICATED WINDS OF 35 TO 40 KT THAT HAVE 
SINCE STRENGTHENED THIS AFTERNOON WITH A SHIP OBSERVATION AROUND 
12/1800 UTC NEAR 14N95W REPORTING 45 KT WINDS AND SEAS TO 20 FT. 
WINDS WILL DIMINISH TO GALE FORCE BY THE END OF THE PERIOD AS 
NORTHERLY WINDS OVER THE GULF OF MEXICO WILL RETURN SOUTHERLY.

WINDS IN THE 20 TO 25 KT RANGE ARE EXPECTED THROUGH THE GULF OF 
PAPAGAYO OVER THE NEXT 48 HOURS AS EASTERLY SURGES IN THE 
SOUTHWESTERN CARIBBEAN SEA BLOW THROUGH THE PASSES.

$$
HUFFMAN