000
AXPZ20 KNHC 020342
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC SUN APR 02 2006

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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY 
THROUGH 0315 UTC.

...ITCZ...
ITCZ AXIS ALONG 4N77W 5N90W 4N110W 5N127W 2N140W. SCATTERED 
MODERATE ISOLATED STRONG WITHIN 90 NM EITHER SIDE OF AXIS 
BETWEEN 86W AND 96W AND WITHIN 60 NM OF 5N122W.

...DISCUSSION...
THE NE PAC IS DOMINATED BY A LONGWAVE TROUGH. AN UPPER CYCLONE 
IS NEAR THE BASE OF THE LONGWAVE TROUGH NEAR 5N121W AND MAY 
POSSIBLY CUT OFF AS THE TROUGH AXIS SHIFTS E. UPPER DIFFLUENCE 
IS ENHANCING CONVECTION NEAR THE CYCLONE CENTER AND WITHIN 420 
NM NW OF CENTER. AN EMBEDDED SHORTWAVE RIDGE ORIGINATES FROM AN 
ANTICYCLONE NEAR 3N162W AND EXTENDS NE ALONG 20N140W TO A CREST 
NEAR 29N127W. THIS RIDGE SEPARATES TWO EMBEDDED SHORTWAVE 
TROUGHS WITHIN THE LARGER PATTERN. THE FIRST TROUGH HAS MOVED 
INLAND THE WESTERN CONUS AND EXTENDS S INTO THE DISCUSSION AREA 
ALONG 32N113W 21N115W. THE SECOND SHORTWAVE IS APPROACHING THE 
NW PORTION AND IS CURRENTLY BECOMING NEGATIVE TILT ALONG 35N142W 
27N140W.   

A BAND OF DRY AIR IS NOTED WITHIN THE LONGWAVE TROUGH WITHIN 60 
NM EITHER SIDE OF LINE 32N103W 25N113W THEN WIDENS COVERING THE 
AREA FROM 22N TO 31N BETWEEN 115W AND 124W THEN NARROWS AGAIN 
INTO THE UPPER RIDGE NEAR 31N131W. 

A BAND OF UPPER MOISTURE RIDES ACROSS THE SHORTWAVE RIDGE THEN 
TURNS CYCLONICALLY NE THROUGH THE LONGWAVE TROUGH...ROUGHLY 
WITHIN 360 NM EITHER SIDE OF LINE 20N140W TO 23N124W WHERE THE 
PLUME NARROWS TO 90 NM WIDE THROUGH 20N116W THEN NE ACROSS OLD 
MEXICO TO BEYOND 32N99W. 

AN UPPER ANTICYCLONE IS CENTERED OVER VENEZUELA WITH A RIDGE 
EXTENDING NW ACROSS THE W CARIBBEAN AND THE EASTERN GULF OF 
MEXICO AND CONTINUING N ACROSS THE SE CONUS. UPPER DIFFLUENCE 
UNDER THIS RIDGE IS ENHANCING CONVECTION NEAR 5N90W WITH THE 
RESULTANT UPPER DEBRIS MOISTURE SPREADING N ACROSS CENTRAL 
AMERICA. OTHERWISE DRY UPPER AIR DOMINATES THE DISCUSSION AREA 
WITHIN 540 NM EITHER SIDE OF LINE 7N140W 24N70W. 

AT THE SURFACE...HIGH PRES 1022 MB IS QUASI STATIONARY NEAR 
27N121W AND IS BLOCKING A WEAKENING FRONTAL TROUGH THAT LIES 
ALONG 32N126W 23N133W. 

GULF OF PAPAGAYO...LATEST SSMI DATA INDICATE NE WINDS 20 KT 
WITHIN 60 NM EITHER SIDE LINE 9N94W 12N87W. THESE NE 20 KT 
WINDS EXPECTED TO CONTINUE THROUGH 48 HOURS. 

$$
NELSON