000
AXPZ20 KNHC 010909
TWDEP 

TROPICAL WEATHER DISCUSSION    
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC SUN APR 01 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 
0845 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 4N77W 7N85W 4N110W 6N122W 2N130W 
3N140W. WIDELY SCATTERED MODERATE CONVECTION WITHIN 45 NM OF THE 
AXIS BETWEEN 86W-95W. SCATTERED MODERATE WITHIN 45 NM OF AXIS 
BETWEEN 114W-130W.

...DISCUSSION...

SUBTROPICAL PACIFIC...
THE MID/UPPER LEVEL FLOW W OF MEXICO IS CHARACTERIZED BY A 
LOW-AMPLITUDE WAVE PATTERN...WITH A WEAK RIDGE CENTERED ALONG 
135W AND A BROAD TROUGH WITH A MEAN AXIS NEAR 118W. THE TROUGH 
IS SOMEWHAT CUT-OFF FROM THE MAIN MID-LATITUDE FLOW WITH THE 
POLAR JET MOVING INLAND OVER THE OREGON/WASHINGTON COAST THEN 
DIPPING SE INTO THE SRN PLAINS. A JET STREAK IN THE SUBTROPICAL 
JET LIES AT THE BASE OF THE TROUGH FROM 23N130W TO 19N110W WITH 
MAXIMUM WINDS OF 100 KT. THE WINDS IN THE JET ARE EXPECTED TO 
QUICKLY WEAKEN TO 60-70 KT WITHIN THE NEXT 12-24 HRS AS THE 
TROUGH SHARPENS OVER THE BAJA PENINSULA. SFC HIGH PRES REMAINS 
IN CONTROL OVER THE AREA IN A WEAKENED STATE...WITH A 1023 MB 
HIGH CENTERED NEAR 34N131W AND THE TRADES SLOWLY DIMINISHING TO 
JUST UNDER 20 KT.

TROPICAL PACIFIC...
A MID-LEVEL HIGH IS CENTERED OVER THE W PART OF THE AREA NEAR 
12N135W BUT IS PRIMARILY COLLOCATED WITH UPPER LEVEL 
WESTERLIES...LIMITING THE AMOUNT OF SUBSIDENCE OCCURRING. WITH 
THE WEAK TROUGH NEAR THE BAJA PENINSULA NOTED ABOVE...PATCHY 
CIRRUS IS BEING ADVECTED ACROSS SOCORRO AND CLARION ISLANDS 
MOVING INLAND ACROSS CENTRAL MEXICO. A LARGER UPPER TROUGH IS 
CENTERED ALONG 98W AND LIES PREDOMINANTLY S OF THE MEXICAN COAST 
WITH MID-LEVEL RIDGING PROTRUDING SW FROM THE YUCATAN PENINSULA. 
THIS IS CAUSING A LARGE AREA OF SUBSIDENCE E OF 110W TO THE 
COAST OF SOUTH AMERICA. MODERATE NORTHERLY FLOW (45 KT) LIES W 
OF THE TROUGH BETWEEN 100W-120W AND MODERATE SOUTHERLY FLOW 
(ALSO NEAR 45 KT) LIES E OF 94W MOVING INTO CENTRAL AMERICA. 
THIS FLOW IS PROVIDING SOME DIVERGENT SUPPORT OVER A SMALL 
CLUSTER OF TSTMS WHICH HAS FORMED ALONG THE ITCZ BETWEEN 86W-95W.

AT THE BEACHES...LONG-PERIOD SW SWELLS (MAX PERIODS NEAR 17 SEC) 
ARE CURRENTLY AFFECTING THE PACIFIC BEACHES FROM COLOMBIA TO 
BAJA CALIFORNIA. A SECOND SWELL TRAIN WITH 17-18 SEC PERIODS IS 
EXPECTED TO REACH THE COAST BEGINNING LATE MON...POSSIBLY WITH 
SLIGHTLY HIGHER WAVE HEIGHTS. DANGEROUS SURF CONDITIONS... 
ESPECIALLY ON SW-FACING BEACHES...ARE LIKELY TO CONTINUE THROUGH 
THE COMING WEEK AS THE SWELLS SLOWLY SUBSIDE.

$$
BERG