000
AXPZ20 KNHC 131003
TWDEP 

TROPICAL WEATHER DISCUSSION    
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC FRI APR 13 2007

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS 
BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND 
METEOROLOGICAL ANALYSIS.

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0815 UTC.

...ITCZ...
AXIS 8N78W 11N98W 4N121W 4N140W. SCATTERED MODERATE ISOLATED 
STRONG CONVECTION WITHIN 180 NM OF AXIS BETWEEN 100W AND 111W.

...DISCUSSION...
UPPER LOW CENTERED OVER ARIZONA IS SLOWLY LIFTING OUT AHEAD OF 
SHARPLY AMPLIFIED MID/UPPER RIDGE AXIS EXTENDING GENERALLY ALONG 
130W N OF 20N. TROUGH EXTENDS FROM THE UPPER LOW TO AROUND 
17N118W. UPPER DIVERGENCE SE OF THE TROUGH IS ENHANCING 
CONVECTION ALONG THE ITCZ AS MENTIONED ABOVE. 

AT THE SURFACE...A TIGHT GRADIENT PERSISTS OFF THE NORTHERN BAJA 
COAST BETWEEN A 1027 MB HIGH CENTERED NEAR 35N130W...AND 997 MB 
LOW PRES CENTERED OVER NEW MEXICO. THIS IS RESULTING IN 
CONTINUING STRONG NLY FLOW OFF THE BAJA COAST ALONG WITH LARGE 
NLY SWELL. FRESH TO STRONG TRADES PERSIST S OF THE HIGH PRES AS 
WELL...GENERALLY N OF 7N AND W OF 125W.

LOOKING AHEAD...THE UPPER LOW WILL LIFT OUT THROUGH THE CENTRAL 
U.S. AS THE RIDGE AXIS SHIFTS EWD OVER THE W COAST...RESULTING 
IN DIMINISHING NLY FLOW OFF BAJA STARTING FRI...ALTHOUGH 
RESIDUAL LARGE SWELL WILL REMAIN. MEANWHILE...AN UPPER TROUGH NE 
OF HAWAII ALONG 150W WILL DIG EWD THROUGH FRI FOLLOWING THE 
UPPER RIDGE. AN ASSOCIATED COLD FRONT WILL PUSH E N OF 
30N...WEAKENING THE SURFACE HIGH. THIS WILL ALLOW TRADES TO 
DIMINISH BRIEFLY...ALTHOUGH EXPECT TRADE STRENGTH TO REBOUND BY 
SAT AS HIGH PRES BUILDS AGAIN TO THE N IN THE WAKE OF THE DYING 
COLD FRONT. FINALLY...ENP WAVEWATCH MODEL CONTINUES TO SHOW 
MODERATE TO LARGE 14S PERIOD WLY SWELL REACHING EXPOSED AREAS OF 
CENTRAL AMERICA AND SRN MEXICO S OF ACAPULCO BY SAT AFTERNOON.

$$
CHRISTENSEN