000
AXPZ20 KNHC 300306
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC WED APR 30 2008

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

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0300 UTC.

...ITCZ...
ITCZ AXIS IS ALONG THE LINE...07N78W TO 10N104W TO 08N115W TO 
06N130W TO 03N140W. SCATTERED MODERATE CONVECTION IS WITHIN 90 
NM EITHER SIDE OF AXIS E OF 82W. SCATTERED MODERATE CONVECTION 
IS WITHIN 180 NM N AND 90 NM S OF AXIS BETWEEN 114W AND 134W. 
SCATTERED MODERATE AND EMBEDDED ISOLATED STRONG CONVECTION 
IS WITHIN 60 NM EITHER SIDE OF AXIS W OF 139W AND WITHIN 120 NM 
N OF AXIS BETWEEN 106W AND 108W.

...DISCUSSION...

E OF 110W...
GALE CONDITIONS ENDED IN THE GULF OF TEHUANTEPEC EARLY TO MIDDAY 
TUE AS NOTED IN 1620 UTC HI-RES ASCAT DATA WHICH SHOWED HIGHEST 
N WINDS NEAR 25 KT. A QSCAT OVERPASS JUST CAME IN OVER THE 
REGION AND IS SHOWING SIMILAR CONDITIONS. THESE WINDS WILL 
CONTINUE TO DIMINISH BECOMING LIGHT BY WED EVENING AS THE HIGH 
PRES SYSTEM IN THE GULF OF MEXICO SHIFTS E INTO THE ATLC 
ALLOWING RETURN FLOW TO DEVELOP OVER THE W HALF OF THE GULF OF 
MEXICO. EARLIER SCATTEROMETER AND SHIP DATA HAVE ALSO SHOWED NE 
TO E 20-25 KT WINDS IN THE GULF OF PAPAGAYO. THIS GAP EVENT IS 
NOT OF THE TYPICAL ORIGIN AS THE CARIBBEAN TRADE WIND FLOW IS 
FAIRLY RELAXED. THE LIKELY TRIGGER IS WEAK CYCLONIC TURNING 
EVIDENT JUST WEST OF COSTA RICA IN EARLIER QSCAT DATA. NWP 
MODELS INDICATE SOME PULSING OF WINDS IN THIS REGION FOR THE 
NEXT 24-36 HOURS. 

ALOFT...A PAIR OF MID-UPPER HIGHS LIE OVER THE REGION. THE MAIN 
HIGH CENTER IS OVER N VENEZUELA AND A SMALLER ONE IS CENTERED 
NEAR 8N98W. A DIFFLUENT PATTERN BETWEEN THESE SYSTEMS IS 
ENHANCING CLOUDINESS AND WIDELY SCATTERED CLUSTERS OF CONVECTION 
WITHIN THE ITCZ E OF 94W. MEANWHILE WAVE MODELS SHOW 17-19 SEC 
SW SWELL APPROACHING THE PACIFIC COASTS OF MEXICO AND CENTRAL 
AMERICA LATE WED AND THU. 

W OF 110W...
THE MID-UPPER PATTERN HAS BECOME INCREASINGLY ZONAL AS A LARGE 
SCALE TROUGH OVER BRITISH COLOMBIA AND THE WESTERN U.S. RIDES TO 
THE N OF A RIDGE OVER THE SUBTROPICS. DEEP LAYER RIDGING IS 
BUILDING E BEHIND THESE FEATURES AND THE ASSOCIATED SFC HIGH 
WILL BE THE PRIMARY FACTOR FOR THE WIND/SEA FORECAST OVER THE 
NEXT COUPLE OF DAYS. THE SURGE OF NW TO N WINDS WILL CONTINUE 
AND SPREAD E TOWARD THE N BAJA COAST WITH ASSOCIATED NW SWELL 
INCREASING SEAS TO 10-12 FT. NE TRADES NEAR 20 TO OCCASIONALLY 
25 KT WILL ALSO BE MAINTAINED OVER THE NEXT 24-48 HOURS. 
ASSOCIATED NE WIND WAVES COMBINED WITH NW SWELL AND 
CROSS-EQUATORIAL SW SWELL WILL PRODUCE A LARGE AREA OF 8-11 FT 
SEAS W OF 130W WED AND THU. FARTHER S...THE UPPER PATTERN 
REMAINS DIFFLUENT ENHANCING A SWATH OF CONVECTION WITHIN ITCZ W 
OF 115W. THIS DIFFLUENT PATTERN IS EXPECTED TO HOLD FOR ATLEAST 
ANOTHER DAY...SO CONVECTION WILL LIKELY CONTINUE TO PULSE IN THE 
SAME VICINITY.

$$
CANGIALOSI