000
AXPZ20 KNHC 151001
TWDEP 

TROPICAL WEATHER DISCUSSION    
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC SUN MAR 15 2009

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 
0900 UTC.

...ITCZ...
AXIS FROM 08N81W TO 03N97W THEN BEGINS ANEW FROM 07N114W TO 
03N140W.  ISOLATED MODERATE CONVECTION WAS WITHIN 90 NM N AND 30 
S OF AXIS BETWEEN 88W AND 95W.

...DISCUSSION...
BROAD NEARLY STATIONARY MID/UPPER LEVEL RIDGE WITH AXIS ALONG 
135W IS ADVECTING ABUNDANT TROPICAL MOISTURE EWD...AND N OF 10N 
OVER ITS CREST.  DOWNSTREAM PERSISTENT LARGE AMPLITUDE UPPER 
LEVEL TROUGH EXTENDING FROM WRN INTERIOR U.S. HAS S/W TROUGH 
SWEEPING SE ACROSS N HALF OF BAJA MEXICO AND INTO NW 
STATES...WITH AN 80-90 KT JET ACROSS THE TOP OF RIDGE AND EWD 
INTO BASE OF THIS TROUGH. ABUNDANT UPPER MOISTURE PICKED UP IN 
PAST FEW DAYS ACROSS THE EPAC IS NOW FARTHER DOWNSTREAM ACROSS 
THE N HALF OF THE GULF OF MEXICO AND THE ENTIRE SERN U.S. A WEAK 
SURFACE TROUGH WAS ALONG 127W FROM 10N-15N AND INTERACTING WITH 
THIS ABUNDANT MOISTURE TO PRODUCE ISOLATED CONVECTION THAT WAS 
BEING STRONGLY SHEARED...AND WEAKENING. ELSEWHERE S OF 17N TO 
95W...SKIES REMAINED NEARLY CLOUD FREE AS BROAD SCALE 
CONVERGENCE ALOFT CONTINUED TO YIELD MODERATE TO STRONG 
SUBSIDENCE W TO 120W.  THIS PATTERN WAS AIDING IN PRODUCING A 
DISCONNECTED ITCZ...WITH A SHORT SEGMENT OFF OF THE COAST OF 
PANAMA...AND ANOTHER BEGINNING FROM 120W WWD. A LARGE AND 
STATIONARY UPPER RIDGE OVER NW SOUTH AMERICA COMPLETES THE UPPER 
LEVEL PICTURE ACROSS THE REGION. 

ELSEWHERE AT THE SURFACE...
A 1026 MB HIGH PRES CENTER NEAR 32N134 ANCHORED A RIDGE AXIS 
EXTENDING SE TO OFFSHORE OF THE W CENTRAL COAST OF MEXICO...AND 
WAS MAINTAINING A MODERATE PRESSURE GRADIENT TO THE N OF THE 
SURFACE TROUGH AND THE ITCZ SEGMENT...YIELDING A NW TO SE 
ALIGNED ZONE OF 20-25 KT WINDS ABOUT 10 DEG WIDE. SEAS ACROSS 
THE ZONE WERE MIXED AND CONFUSED IN MERGING NW AND S LONG 
PERIOD SWELL...AND ENE WIND WAVES...AND WILL GRADUALLY DIMINISH 
DURING THE NEXT 24-36 HOURS AS THE SWELLS SLOWLY FADE. THE HIGH 
PRESSURE RIDGE WAS ALSO INDUCING 20-25 KT WINDS OFF OF THE W 
COAST OF BAJA CALIFORNIA AS DEPICTED BY AN EVENING QUIKSCAT 
PASS...WHICH WAS COMBINING WITH NWLY SWELL TO PRODUCE SEAS TO 9 
FT BETWEEN 30N AND 25N. 

A HIGH PRES RIDGE CENTERED ACROSS THE W CENTRAL ATLC WILL 
SETTLE SLIGHTLY SW OVER THE NEXT FEW DAYS AND INCREASE WINDS 
20-25 KT ACROSS THE CENTRAL AND SW CARIB...WHICH IN TURN WILL 
CAUSE GAP WINDS THROUGH THE GULFS OF PAPAGAYO AND PANAMA TO 
PULSE UP AND DOWN AT OR ABOVE 20 KT...SEEN MOST SIGNIFICANTLY 
ACROSS PAPAGAYO...WHERE WINDS HAVE JUST INCREASED TO 20 KT AGAIN 
LATE THIS EVENING. 

$$

STRIPLING