000
AXPZ20 KNHC 261510
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC SUN APR 26 2009

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

BASED ON 1500 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC.

...ITCZ...
AXIS IS ALONG 3N78W 7N100W 5N135W 4N140W. SCATTERED MODERATE 
ISOLATED STRONG CONVECTION WITHIN 60 NM N OF AXIS FROM 
117W-121W. SCATTERED STRONG CONVECTION WITHIN 120 NM N OF AXIS 
FROM 123W-131W.


...DISCUSSION...
A PERSISTENT STRONG FULL LATITUDE TROUGH REMAINS W OF THE AREA.
A BROAD PLUME OF DEEP LAYER MOISTURE AND OVERCAST MULTI LEVEL 
CLOUDS IS W OF 130W IS ASSOCIATED WITH THIS FEATURE. THE 
UPPER FLOW IS DIFFLUENT AND HAS CONTRIBUTED TO THE DEVELOPMENT 
OF A LARGE AREA OF CONVECTION AND A SURFACE TROUGH N OF THE ITCZ 
FROM 5N131W TO 12N140W. THE DIFFLUENT FLOW ALOFT IS ALSO 
ENHANCING CONVECTION ALONG THE ITCZ DESCRIBED ABOVE. THE 
CONVECTION N OF THE ITCZ IS FROM 7N-17N BETWEEN 130W-136W.
AN UPPER LEVEL RIDGE E OF THE TROUGH EXTENDS FROM 32N129W TO 
15N125W THEN SW TO 8N130W.

MID/UPPER LEVEL SHORTWAVE TROUGH WITH AXIS FROM SOUTHERN ARIZONA 
TO THE TIP OF THE BAJA PENINSULA IS MOVING RAPIDLY E. THIS 
FEATURE WILL CONTINUE ACROSS NORTHERN MEXICO N OF 25N THROUGH 
TONIGHT THEN BE ABSORBED BY THE WESTERLIES AS IT APPROACHES 
TEXAS MON. ONLY A FEW CLOUDS ARE E OF THE TROUGH AXIS.

A SHARP MID/UPPER LEVEL RIDGE EXTENDS FROM THE NW GULF OF MEXICO 
ACROSS CENTRAL MEXICO TO 15N104W. DOWNSTREAM MID/UPPER LEVEL
TROUGH EXTENDS FROM THE WESTERN YUCATAN PENINSULA THROUGH THE 
GULF OF TEHUANTEPEC TO 12N96W. THE AIRMASS IS RATHER MOIST E OF 
THE TROUGH...WITH STRONG SUBSIDENCE AND DRY STABLE AIR IS BETWEEN
THE TROUGH AND THE RIDGE.

SURFACE RIDGE IS N OF 14N W OF 110W. NE TO E WINDS CONTINUE TO 
BLOW THROUGH THE GULF OF PAPAGAYO...BUT HAVE DECREASED A LITTLE
FROM THE LAST FEW DAYS.

$$
DGS