000
AXPZ20 KNHC 112206
TWDEP 

TROPICAL WEATHER DISCUSSION   
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC MON APR 11 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 
2115 UTC.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE AXIS WAS ANALYZED FROM 06N78W 
TO 07N95W WITH A BREAK AND CONTINUING AGAIN FROM 06N104W TO 
04N114W TO 05N128W WITH A BREAK AND CONTINUING AGAIN FROM 
03N132W TO EQUATOR AT 134W. SCATTERED MODERATE ISOLATED STRONG 
CONVECTION WITHIN 120 NM S OF AXIS BETWEEN 80W AND 92W. 
SCATTERED MODERATE ISOLATED STRONG CONVECTION WITHIN 180 NM OF 
AXIS BETWEEN 104W AND 113W.

...DISCUSSION...

SURFACE FEATURES...
A 1034 MB SURFACE HIGH AT 37N143W NORTH OF OUR AREA IS HELPING 
TO PRODUCE WINDS OF 20 KT THROUGHOUT MUCH OF THE REGION N OF 07N 
AND W OF 115W.  WEST OF BAJA CALIFORNIA NW WINDS WERE OBSERVED 
BY BOTH A 1332Z WINDSAT PASS AS WELL AS FROM SHIP 9HJD9.  20 KT 
NE TRADEWINDS S OF 22N W OF 115W ARE ALSO RESULTING FROM THE 
GRADIENT PRODUCED BY THE SURFACE HIGH.  AS THE SYNOPTIC PATTERN 
CHANGES LITTLE DURING THE NEXT FEW DAYS...THIS WINDS SHOULD 
CONTINUE. SIGNIFICANT WAVE HEIGHTS ACCOMPANYING THESE WINDS ARE 
UP TO 11 FT.

SURFACE WINDS HAVE ALSO BEEN ENHANCED IN THE GULF OF CALIFORNIA 
TODAY WITH PEAK NW WINDS INDICATED BY THE 1332Z WINDSAT PASS OF 
25 TO 30 KT AROUND 27N TO 29N.  AS THE FORCING HAS LIKELY 
DIMINISHED SOME SINCE THAT TIME...CURRENT WINDS ARE ESTIMATED TO 
BE 20 TO 25 KT N OF 25N.  THESE SHOULD DROP BELOW THE 20 KT 
THRESHOLD BY TUESDAY MORNING.

A 1011 MB LOW IS LOCATED NEAR 07N100W.  WHILE THIS HAS A 
SUBSTANTIAL CIRCULATION ASSOCIATED WITH IT...THERE IS CURRENTLY 
NO DEEP CONVECTION AND IT IS LIKELY TO DISSIPATE WITHIN THE NEXT 
DAY OR SO.  A TROUGH SOUTH OF 10N ALONG 130W ALSO SHOWS QUITE A 
BIT OF ROTATION TODAY AND HAS SCATTERED MODERATE ISOLATED STRONG 
CONVECTION WITHIN 180 NM OF AXIS.  HOWEVER...THIS SYSTEM IS NOT 
LIKELY TO BECOME A PRE-SEASON TROPICAL CYCLONE DUE TO THE STRONG 
VERTICAL SHEAR CURRENTLY SCOURING THE TROPICAL NE PACIFIC WEST 
OF 120W.

A BRIEF WEAK NW SWELL EVENT WITH PEAK SIGNIFICANT WAVE HEIGHTS 
OF 8 TO 9 FT SHOULD REACH OUR NW CORNER IN ABOUT A DAY AND JUST 
LAST THROUGH WEDNESDAY.

GAP WIND EVENTS...
A WEAK...NE 20 KT...GULF OF PAPAGAYO WIND EVENT IS INDICATED IN 
THE HIGH SEAS FORECAST TO CONTINUE FOR THE NEXT TWO OR THREE 
DAYS.  AS IS TYPICAL FOR THESE MARGINAL EVENTS...THE WINDS ARE 
STRONGEST IN THE MORNING HOURS.

A MODERATE...N 20 TO 25 KT...GULF OF TEHUANTEPEC WIND EVENT 
SHOULD COMMENCE IN ABOUT 24 HOURS...PERHAPS SLIGHTLY EARLIER IF 
THE GFS IS CORRECT...SLIGHTLY LATER IF THE ECMWF IS CORRECT.  
THIS IS UNLIKELY TO REACH GALE FORCE CONDITIONS AND SHOULD DROP 
BELOW THE 20 KT THRESHOLD LATE ON WEDNESDAY.

UPPER LEVELS...
A SHORT WAVE TROUGH IN THE MID AND UPPER LEVELS IS MOVING 
EASTWARD THROUGH 128W N OF 25N...SUPPORTING A WEAKENING SURFACE 
COLD FRONT EXTENDING FROM NORTHERN CALIFORNIA TO 31N131W. THE 
UPPER SHORT WAVE TROUGH WILL FLATTEN OUT THROUGH EARLY TUE AS 
UPPER LEVEL JET ENERGY DIGS A NEW SHORT WAVE TROUGH TO THE WEST 
ALONG 140W N OF 20N.

$$
LANDSEA