000
AXPZ20 KNHC 120904
TWDEP 

TROPICAL WEATHER DISCUSSION    
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC WED APR 11 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 0815 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0600 UTC.

...ITCZ...
AXIS 10N85W 8N94W 8N110W 5N117W 2N140W. SCATTERED MODERATE 
CONVECTION WITHIN 60 NM OF 8N94W.

...DISCUSSION...
AMPLIFIED PATTERN REMAINS IN PLACE WITH MID/UPPER TROUGH 
EXTENDING FROM SOUTHERN CALIFORNIA TO NEAR 19N126W...AHEAD OF A 
LARGE UPPER RIDGE BUILDING ALONG 140W GENERALLY N OF 30N. AT THE 
SURFACE...A 1030 MB HIGH IS CENTERED N OF THE DISCUSSION AREA 
NEAR 33N137W. A 1000 MB LOW PRESSURE CENTERED IS NOTED OVER THE 
INTERIOR AREAS OF SOUTHERN CALIFORNIA. THE TIGHT GRADIENT 
BETWEEN THESE TWO PRESSURE SYSTEMS IS ALLOWING FRESH TO STRONG 
NLY FLOW OFF THE NORTHERN COAST OF BAJA CALIFORNIA. A WEAK COLD 
FRONT IS ACCOMPANYING THE NLY FLOW...BUT WILL QUICKLY WASH OUT 
AS IT MOVES S. MEANWHILE RECENT SHIP OBSERVATIONS AND EVENING 
QUIKSCAT DATA SHOW PERSISTENT FRESH TRADES S OF THE HIGH 
PRES...BUT FAIRLY LIGHT FLOW PREVAILING ALONG THE ITCZ AND 
COASTAL REGIONS OF SOUTHERN MEXICO AND CENTRAL AMERICA. 

LOOKING AHEAD TO THE NEXT COUPLE OF DAYS...THE UPPER FLOW WILL 
REMAIN FAIRLY PROGRESSIVE AS UPPER RIDGE BUILDS EWD. WINDS OFF 
THE NRN BAJA COAST WILL GRADUALLY DIMINISH THU INTO FRI AS THE 
SURFACE LOW PRES OVER THE DESERT S.W. LIFTS OUT ALONG WITH THE 
UPPER TROUGH...AHEAD OF THE ADVANCING UPPER RIDGE AND ASSOCIATED 
WEAKENED SURFACE HIGH. TRADES BRIEFLY RELAX FRI INTO SAT AS THE 
HIGH PRES WEAKENS...BEFORE STRENGTHENING AGAIN THIS WEEKEND.

CHRISTENSEN