000
AXPZ20 KNHC 261551
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC WED JAN 26 2011

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...

AXIS EXTENDS FROM AXIS 05N77W TO 06N90W TO 08N135W TO 07N140W. 
SCATTERED MODERATE TO ISOLATED STRONG CONVECTION WITHIN 60 NM 
EITHER SIDE OF AXIS E OF 79W.

...DISCUSSION...

W OF 110W...A FAIRLY AMPLIFIED UPPER PATTERN REMAINS IN PLACE N 
OF 20N. AN UPPER TROUGH EXTENDS FROM NORTHERN BAJA TO 
24N135W...THEN S TO 13N142W. ANOTHER UPPER TROUGH WITH AN 
ASSOCIATES COLD FRONT IS DIGGING EASTWARD THROUGH 145W N OF 
20N...RESULTING IN VERY SHARP UPPER RIDGE BETWEEN THE TWO TROUGH 
EXTENDING FROM THE COAST OF WASHINGTON TO 26N140W. AN ASSOCIATED 
1021 MB SURFACE HIGH PRES AREA CENTERED N OF THE AREA NEAR 
40N130W...WILL SHIFT S TO 28N137W BY EARLY THU...BLOCKING THE 
ADVANCE OF THE COLD FRONT WHICH WILL DISSIPATE NW OF THE AREA 
THROUGH LATE THU AS THE UPPER SUPPORTING TROUGH LIFTS TO THE NE. 
MEANWHILE THE SOUTHERN EXTENT OF THE UPPER TROUGH FROM NORTHERN 
BAJA TO 12N142W BECOMES CUTOFF NEAR 13N145W ON THU. AN 
ASSOCIATED SURFACE TROUGH CURRENTLY W OF 140W BECOMES MORE 
PRONOUNCED BY THU AS THE UPPER LOW CUTS OFF. THE SURFACE HIGH 
PRES DROPS SOUTH AT THE SAME TIME...ALLOWING FOR FRESH TO STRONG 
TRADES BETWEEN THE TROUGH AND THE HIGH PRES...WITH SEAS BUILDING 
TO AS HIGH AS 13 FT IN MIXED NW SWELL AND WIND WAVES. MEANWHILE 
NW SWELL OF 10 FT OR GREATER IS MOVING INTO THE NW PORTION OF 
THE DISCUSSION AREA...REINFORCING AN EARLY GROUP OF NW SWELL OF 
8 TO 9 FT CURRENTLY MOVING ACROSS THE WHOLE AREA.

E OF 110W...THE MAIN ISSUE IS STRONG GAP WIND FLOW THROUGH THE 
GULF OF TEHUANTEPEC AS A COLD AIRMASS PUSHES INTO THE SW GULF OF 
MEXICO. LATEST OBSERVATIONS FROM IXTEPEC ON THE SOUTH SIDE OF 
THE ISTHMUS SHOW 25 KT WINDS...HINTING OF 30 KT OVER WATER. IN 
ADDITION...EXPERIMENTAL COASTAL ASCAT DATA FROM 03Z SHOWED 20 TO 
25 KT WINDS ALREADY STARTING ALONG THE COAST. THE 06Z GFS SHOWS 
30 METER WINDS REACHING MINIMAL GALE FORCE FOR BRIEF PERIOD 
DURING THE OVERNIGHT HOURS...LIKELY DUE TO DRAINAGE EFFECTS. 
HOWEVER...ECMWF MAINTAINS BELOW GALE FORCE AT 30 KT. FORECAST 
WILL MAINTAIN CONTINUITY AND KEEP CONDITIONS BELOW GALE FORCE 
THROUGH 48 HOURS. THE STRONG TEHUANTEPEC FLOW WILL GENERATE NE 
SWELL BY THU...THAT WILL MIX WITH AN AREA OF DECAYING NW SWELL 
GENERALLY S OF 14N BETWEEN 90W AND 110W. MEANWHILE...WINDS 
THROUGH PAPAGAYO WILL PULSE TO 20 KT IN MAINLY THE OVERNIGHT AND 
EARLY MORNING HOURS THROUGH FRI. 

GULF OF CALIFORNIA...HIGH PRES BUILDING OVER THE GREAT BASIN 
WILL IMPART FRESH TO STRONG NW FLOW OVER MAINLY THE NORTHERN 
GULF OF CALIFORNIA THROUGH FRI.

$$

CHRISTENSEN