000
AXPZ20 KNHC 231556
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC FRI APR 23 2010

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 
1200 UTC.

...ITCZ...
AXIS ALONG 05N77W TO 05N100W TO 07N107W TO 04N122W TO 07N130W TO 
05N140W.  ISOLATED MODERATE WITHIN 180 NM OF AXIS BETWEEN 91W 
AND 95W AND 90 NM OF AXIS E OF 80W. 
 
...DISCUSSION...
AT THE SURFACE...A BROAD 1030 MB HIGH IS NORTHWEST OF OUR AREA.  
AN ENHANCED GRADIENT BETWEEN IT AND THE LOW PRESSURE OVER THE 
SOUTHWEST UNITED STATES IS PRODUCING SOME MODERATE 20 KT W TO N 
WINDS IN THE GULF OF CALIFORNIA AND IN THE PACIFIC EAST OF 
130W.  AS THE LOW ADVECTS EASTWARD...THE FORCING WILL DIMINISH 
AND WINDS SHOULD DROP BELOW OUR 20 KT THRESHOLD BY TOMORROW 
MORNING IN BOTH LOCATIONS.  

MODERATE E TO NE TRADEWIND FLOW OF ABOUT 20 KT W OF 125W BETWEEN 
10N AND 20N WILL CONTINUE ON SATURDAY...BUT DIMINISH ON SUNDAY 
AS THE HIGH NORTHWEST OF THE AREA WEAKENS AND MOVES EASTWARD.

NO SIGNIFICANT GAP WIND EVENTS ARE OCCURRING...NOR LIKELY TO 
OCCUR DURING THE NEXT FEW DAYS.  

A WEAK 1006 MB LOW HAS FORMED NEAR 05N79W...JUST SOUTH OF 
PANAMA...AND IS ACCOMPANIED BY SOME ISOLATED MODERATE 
CONVECTION.  THE 06 UTC GFS QUICKLY SPINS UP THIS SYSTEM AND 
PROJECTS 30 KT SW WINDS S AND SW OF THE LOW ON SATURDAY.  THE 06 
UTC NOGAPS AND 00 UTC UKMET DO NOT INDICATE ANY LOW 
FORMING...WHILE THE 00 UTC ECMWF SPLITS THE DIFFERENCE WITH 
CONTINUING A WEAK LOW FOR THE NEXT 36 HOURS.  MY FORECAST IS 
CLOSEST TO THE ECMWF SOLUTION.

SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS OCCURRING 
IN ASSOCIATION WITH A TROUGH ALONG 110W.  BECAUSE OF STRONG SW 
VERTICAL SHEAR AND LITTLE SUPPORTING SYNOPTIC SCALE 
VORTICITY...FURTHER DEVELOPMENT OF THIS SYSTEM IS NOT LIKELY.

MOST OF THE REGION IS DOMINATED BY NW SWELL PRODUCED BY THE TWO 
VIGOROUS LOWS IN THE GULF OF ALASKA.  WHILE HIGHEST SIGNIFICANT 
WAVE HEIGHTS ARE UP TO 15 FEET WEST BAJA CALIFORNIA 
CURRENTLY...THESE SHOULD GRADUALLY SUBSIDE TO BELOW 10 FEET OVER 
NEARLY THE ENTIRE AREA BY MONDAY.  ON MONDAY...SW SWELL FROM THE 
SOUTHERN HEMISPHERE WILL BEGIN REACHING THE SOUTHERN BOUNDARY 
WITH SIGNIFICANT WAVE HEIGHTS UP TO 11 FEET.

$$
LANDSEA