000
AXPZ20 KNHC 031530
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC SAT APR 03 2010

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

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1330 UTC.

...ITCZ...
THE INTERTROPICAL CONVERGENCE ZONE WAS ANALYZED ALONG 05N77W TO 
06N95W TO 04N105W TO 04N131W TO 05N140W. SCATTERED MODERATE WITH 
ISOLATED STRONG CONVECTION WAS WITHIN 90 NM S AND 30 NM N OF THE 
ITCZ AXIS BETWEEN 82W AND 93W. SCATTERED MODERATE CONVECTION WAS 
WITHIN 150 NM S OF THE ITCZ AXIS BETWEEN 117W AND 129W AS WELL 
AS WITHIN 180 NM N OF THE ITCZ AXIS W OF 138W.


...DISCUSSION...
A WEAK SOUTHERN STREAM UPPER TROUGH CURRENTLY LIES FROM 26N117W 
TO 19N125W TO 14N134W. AN 80 KT SOUTHWESTERLY UPPER JET LIES ON 
THE SE SIDE OF THE TROUGH AXIS AND IS TRANSPORTING TROPICAL MID 
TO UPPER LEVEL MOISTURE...MANIFESTED AS SCATTERED CIRRUS 
CLOUDS...NORTHEASTWARD FROM THE ITCZ BETWEEN 120W AND 135W INTO 
CENTRAL MEXICO. UPPER LEVEL DIFFLUENCE BETWEEN THIS JET AND A 40 
KT NORTHWESTERLY JET FROM 00N135W TO 10S115W AND CONTINUING SE 
IS GENERATING VERTICAL LIFT WITHIN 300 NM OF 06N116W. A SURFACE 
TROUGH IS EMBEDDED IN THE ITCZ ALONG 116W IN THIS AREA...BUT 
ONLY SCATTERED MODERATE CONVECTION IS NOTED ALONG THE ITCZ W OF 
THE TROUGH. PRECIPITABLE WATER SATELLITE IMAGERY SHOWS LOW TO 
MID LEVEL MOISTURE IS DIMINISHING IN THE REGION AND MAY BE 
LIMITING THE CONVECTION HERE. AN ANTICYCLONE LIES TO THE E OF 
THIS REGION CENTERED NEAR 06N103W OVER A RELATIVE PRECIPITABLE 
WATER MINIMUM ALONG THE ITCZ AND HAS LITTLE CONVECTION DESPITE 
THE UPPER LEVEL DIFFLUENCE ASSOCIATED WITH IT. THE STRONGEST 
CONVECTION ALONG THE ITCZ IS BETWEEN 82W AND 93W UNDER A REGION 
OF LIGHT UPPER LEVEL WINDS BUT STRONG LOW LEVEL MOSITURE 
CONVERGENCE. DIFFLUENCE ALOFT BETWEEN A DEEP-LAYERED TROUGH 
EXTENDING SW INTO THE SW CARIBBEAN AND A RIDGE AXIS OVER 
NORTHERN COLOMBIA IS ALSO GENERATING SCATTERED MODERATE 
CONVECTION NEAR THE W COAST OF COLOMBIA AND THE SW COAST OF 
COSTA RICA. WINDS IN THE GULF OF PAPAGAYO ARE LIGHT AND VARIABLE 
ACCORDING TO THE 0240 UTC ASCAT PASS...BUT THEY ARE EXPECTED TO 
INCREASE TO 25 KT MON MORNING AS HIGH PRES BUILDS TO THE N OVER 
CENTRAL AMERICA AND INCREASES THE PRES GRADIENT BETWEEN IT AND 
CLIMATOLOGICAL LOW PRES OVER COLOMBIA. FARTHER N...THE 
SUBTROPICAL HIGH IS SHIFTED WELL W OF THE AREA NEAR 31N171W. A 
COLD FRONT OVER THE GREAT BASIN EXTENDS W AS A WEAKENING 
STATIONARY BOUNDARY JUST N OF THE AREA...ENCROACHING ON THE 
WESTERN EDGE OF ITS SURFACE RIDGE. THE PRES GRADIENT BETWEEN 
LOWER PRES OVER THE GREAT BASIN AND THE RIDGE AXIS S OF THE 
DISSIPATING BOUNDARY IS GENERATING NW TO N WINDS TO 25 KT ALONG 
THE W COAST OF BAJA CALIFORNIA. THESE WINDS WILL CONTINUE 
THROUGH THE FORECAST PERIOD AS THE LOW PRES IN THE WESTERN U.S. 
IS REINFORCED BY A NEW NORTHERN STREAM SYSTEM SUN NIGHT INTO 
MON. THE RIDGE AXIS OVER FORECAST WATERS WILL BY WEAKENED BY THE 
DISSIPATING STATIONARY BOUNDARY TODAY AND TRADE WINDS TO ITS S 
WILL SHRINK BOTH S AND W BY SUN MORNING. THE 0604 UTC ASCAT PASS 
CURRENTLY SHOWS THE TRADE WIND ZONE FROM 07N TO 24N W OF 120W.

FOR ADDITIONAL INFORMATION PLEASE VISIT 
HTTP://WWW.HURRICANES.GOV/MARINE

$$
SCHAUER