000
AXPZ20 KNHC 260945
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC MON APR 26 2010

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 
0930 UTC.

...ITCZ...
AXIS ALONG 08N81W TO 05N102W TO 07N124W TO 05N140W.  SCATTERED 
MODERATE ISOLATED STRONG CONVECTION WITHIN 180 NM N AND 90 NM S 
OF AXIS E OF 107W.  ISOLATED MODERATE CONVECTION WITHIN 120 NM 
OF AXIS W OF 113W.

...DISCUSSION...
SHARP UPPER LEVEL TROUGH FROM 32N125W TO 19N140W INTRODUCES DRY 
AIR MASS WITHIN 240 NM OF AXIS INTO E PAC JUST UPSTREAM FROM 135 
KT JET CORE ADVECTING LONG SWATH OF TROPICAL MOISTURE ACROSS 
BASIN FROM SW CORNER TO BAJA CALIFORNIA AND NORTHERN MEXICO. 
BROAD MID/UPPER LEVEL RIDGE CENTERED AT 13N106W MAINTAINS 
MOISTURE ON ITS WESTERN PERIPHERY OVER ITS CREST AND ON ITS 
SOUTHERN FRINGES ALONG ITCZ.  WEAK UPPER LEVEL TROUGH FROM GULF 
OF HONDURAS TO GALAPAGOS ISLANDS OSCILLATES OVER SE CORNER OF 
BASIN PROMPTING UPPER LEVEL DIFFLUENCE ON TOP OF HIGHLY UNSTABLE 
MOIST AIR MASS.  AREAS OF DEEP CONVECTION FORM AND DRIFT W AWAY 
FROM REGION ALONG ITCZ WHICH IS BECOMING MORE ACTIVE.  ENHANCED 
VORTICITY E OF 90W MAKES REGION RIPE FOR MORE TROPICAL ACTION.

ELSEWHERE AT THE SURFACE...
HIGH PRES CENTER 1024 MB AT 28N138W WEAKENS TODAY AND DISSIPATES 
TONIGHT EFFECTIVELY TRUMPING NE TRADES W OF 130W BELOW 20 KT.
COLD FRONT IMPINGING UPON NW CORNER OF BASIN SHOULD SIMILARLY 
WEAKEN TODAY AND BECOME DIFFUSE TONIGHT WITH NO SIGNIFICANT WIND 
EFFECTS BUT BRINGING SURGE OF LARGE LONG PERIOD NW SWELL WITH 
HEIGHTS TO 10 FT.  NW SWELLS MERGE WITH CROSS-EQUATORIAL SW 
SWELL ACROSS TROPICS S OF 10N THROUGH WED. 

$$
WALLY BARNES