000
AXPZ20 KNHC 300857
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC SUN MAR 30 2008

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

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY 
THROUGH 0830 UTC.

...ITCZ...

ITCZ AXIS IS ALONG 5N93W 3N105W 5N120W 4N130W 4N140W. SCATTERED 
MODERATE WITHIN 150 NM N OF AXIS BETWEEN 119W AND 127W. 
SCATTERED MODERATE ISOLATED STRONG WITHIN 140 NM N OF AXIS 
BETWEEN 134W AND 138W.

...DISCUSSION...

A LARGE AMPLITUDE MID TO UPPER TROPOSPHERIC TROUGH EXTENDS FROM 
NORTHERN CA SOUTHWESTWARD OVER THE NW DISCUSSION AREA NEAR 
21N140W. THE TROUGH IS EXPECTED TO SLOWLY DRIFT NE AND FILL WITH 
THE PATTERN BECOMING MORE ZONAL OVER THE NORTHERN AREA BY MON. 
NEXT SIGNIFICANT PULSE SHOULD ENTER THE NW AREA AROUND MON 
NIGHT. DURING THE PAST 48 HOURS...A LARGE PLUME OF MID TO 
UPPER MOISTURE ASSOCIATED WITH A SUBTROPICAL JET FINGER HAS 
PROPAGATED SOUTH OF BAJA CALIFORNIA AND IS CURRENTLY SPREADING 
OVER THE CENTRAL PORTIONS OF MX. CONSEQUENTLY...MODERATE 
SUBSIDENCE HAS REPLACED THE PLUME OVER THE PENINSULA. DRY STABLE 
CONDITIONS PERSIST ALONG THE COASTS OF SOUTHERN MX/CENTRAL 
AMERICA AND ADJACENT WATERS AS CONDITIONS ALOFT MAINTAIN A 
RATHER STAGNANT STATE. LITTLE...IF ANY...CHANGE IS EXPECTED 
DURING THE NEXT FEW DAYS.
    
AT THE SURFACE...HIGH PRESSURE RIDGE CONTINUES TO DOMINATE N OF 
10N WITH ASSOCIATED N TO NE 20 KT WINDS GENERATING 8-10 FT 
SWELLS. SEAS ARE EXPECTED TO SUBSIDE TO 8 FT OR LESS BY MON EVE 
AS THE RIDGE BREAKS DOWN AND SHIFTS NE. SEAS SHOULD GRADUALLY 
BEGIN TO BUILD LATE TUE NIGHT AS NEXT FRONTAL SYSTEM APPROACHES 
NW OF DISCUSSION AREA. A SURFACE TROUGH EXTENDS NORTHEASTWARD 
TOWARD THE COAST OF COSTA RICA FROM A 1008 MB LOW NEAR 5N93W. 
THIS FEATURE IS TRIGGERING SCATTERED MODERATE TO ISOLATED STRONG 
DEEP CONVECTION FROM 3N TO 6N BETWEEN 87W AND 90W. THE SHOWER 
AND STRONG THUNDERSTORM ACTIVITY APPEAR TO BE ASSOCIATED MORE 
WITH THE SURFACE TROUGH AND IS DISPLACED BY MORE THAN 225 NM 
FROM THE LOW CENTER. ACTIVITY ASSOCIATED WITH THE LOW IS QUITE 
LIMITED AND SHALLOW. ELSEWHERE...THE ITCZ IS A BIT ACTIVE THIS 
EVENING OVER THE SW PORTION OF THE AREA...W OF 115W...AND 
BENEATH THE WESTERN EXTENT OF A NARROW UPPER RIDGE STRETCHING 
WEST-SOUTHWESTWARD FROM SOUTHERN MX. 

$$
ROBERTS