000
AXPZ20 KNHC 242205
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC FRI APR 24 2009

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 
2315 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 4N77W 5N90W 6N100W 4N110W 6N120W
6N130W 5N140W. SCATTERED MODERATE CONVECTION EXISTS FROM
5N-11N BETWEEN 121W-125W...WITHIN 45 NM N OF THE AXIS BETWEEN
82W-85W AND BETWEEN 104W-107W.

...DISCUSSION...

MID/UPPER LEVEL RIDGE EXTENDS FROM THE SW U.S. SW ACROSS
NW MEXICO TO ACROSS CENTRAL AND SRN BAJA CALIFORNIA TO 18N114W
TO NEAR 11N119W. THIS FEATURE CONTINUES TO BE THE MOST 
PREDOMINATE IN THE AREA SEPARATING THE REGION FROM TROUGHS TO 
ITS E AND NW. THE TROUGH TO THE E STRETCHES FROM NE MEXICO
SW TO 19N102W TO 10N105W TO NEAR 06N107W. A STRONG DEEP LAYER
TROUGH W OF THE REGION IS DIGGING SSE TOWARDS HAWAII WITH AN
ASSOCIATED UPPER LEVEL LOW ALSO W OF THE AREA NEAR 29N156W.
ALTHOUGH THIS CLEARLY DEFINED FEATURE IS W OF THE AREA...THE
DIFFLUENT PATTERN OBSERVED TO ITS ESE IS ENHANCING CONVECTION
WITHIN 300 NM SE OF THE TROUGH. DUE TO THE CURRENT PLACEMENT OF
THE TROUGH AND RIDGE...THE RESULTANT MODERATE TO STRONG UPPER 
FLOW BETWEEN THESE TWO FEATURES IS ADVECTING ABUNDANT MID AND 
UPPER LEVEL CLOUDINESS RELATED TO CONVECTION W OF THE AREA UNDER 
THE DIFFLUENT ENE TO JUST E OF 140W N OF 15N. A WEAK SURFACE 
TROUGH ENTERS THE AREA THROUGH 32N133W...AND CONTINUES SW TO W 
OF THE AREA NEAR 26N140W. MOSTLY BROKEN LOW AND MID CLOUDS WITH 
POSSIBLE WIDELY SCATTERED SHOWERS ARE WITHIN 30 NM OF THE 
TROUGH. THIS TROUGH WILL DISSIPATE THROUGH SAT NIGHT AS STRONG 
HIGH PRES BUILDS SEWD INTO THE AREA.

THE TROUGH OVER THE ERN PART OF THE AREA IS SLIGHTLY ENHANCING 
ITCZ CONVECTION BETWEEN 90W-103W DUE TO MODERATE SUBSIDENCE AND 
STABLE ENVIRONMENTAL CONDITIONS FOUND THERE. THE MID/UPPER LEVEL 
RIDGE WILL BE NUDGED EWD AND GRADUALLY DAMPEN OUT THROUGH SUN
AS THE TROUGH AND LOW W OF THE AREA LIFT N INTO A LARGER TROUGH
THAT DIGS SEWD.

AT THE SURFACE...A 1021 MB HIGH CENTERED NEAR 27N131W EXTENDS A 
RIDGE SE TO 22N119W TO 19N109W. HIGH PRES COVERS THE AREA N OF 
14N AND W OF 110W. AS HIGH PRES STRENGTHEN THROUGH SUN...THE
PRES GRADIENT TIGHTENS OVER THE NE WATERS LEADING TO AN INCREASE 
IN NW-N WINDS (ABOUT 20 KT) NEAR THE BAJA CALIFORNIA COAST.

A WEAK SURFACE TROUGH VOID OF ANY DEEP CONVECTION IS ALONG 99W 
FROM 4N-9N IS MOVING W 10-15 KT. 

BROKEN TO OVERCAST STRATOCUMULUS CLOUDS ARE NOTED NW OF LINE 
FROM 26N114W TO 19N125W TO 17N136W.

GAP WINDS...
NE WINDS OF 20-25 KT IN THE GULF OF PAPAGAYO ARE FORECAST TO 
WEAKEN TO 20 KT IN 48 HRS WITH SEAS CURRENTLY IN THE 8 TO 10 FT 
RANGE FORECAST TO SUBSIDE TO 8 FT OR LESS.

$$
AGUIRRE