000
AXPZ20 KNHC 270937
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC THU APR 27 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0845 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 7N77W 8N85W 11N96W 9N107W 9N120W 
5N140W. SCATTERED MODERATE CONVECTION WITHIN 90 NM OF THE AXIS 
BETWEEN 86W-89W...BETWEEN 125W-130W...AND BETWEEN 135W-140W.

...DISCUSSION...

N OF 20N...
MID/UPPER LEVEL LOW IS CENTERED JUST N OF THE AREA OFF THE SRN 
CA/NRN BAJA COAST NEAR 31N118W MOVING ESE 10-15 KT. A MID-LEVEL 
BAROCLINIC BOUNDARY...THE ELEVATED PACIFIC FRONT...HAS SURGED 
EWD AHEAD OF THE LOW EXTENDING FROM S/CNTRL ARIZONA TO THE CNTRL 
BAJA PENINSULA AS SEEN IN WATER VAPOR IMAGERY. THE ASSOCIATED 
SURFACE PRESSURE TROUGH HAS ALSO MOVED INLAND BUT IS NOT 
WELL-DEFINED. SCATTERED SHOWERS ARE LOCATED WITHIN 200 NM OF THE 
UPPER LOW AND ARE JUST BEGINNING TO DROP S OF 30N BETWEEN 
116W-121W. ELSEWHERE...THE UPPER TROUGH AXIS LAGS WWD FROM THE 
LOW TO 20N140W. CONFLUENCE NEAR THIS AXIS IS PRODUCING A LARGE 
AREA OF STRONG SUBSIDENCE FROM 15N-26N W OF 120W.

S OF 20N AND OVER MEXICO...
THE SUBTROPICAL JET LIES ON THE SE SIDE OF THE MID/UPPER LOW 
DESCRIBED ABOVE...EXTENDING FROM 15N130W TO 28N110W OVER NW 
MEXICO. JET CORE SPEEDS ARE NOT ALL THAT IMPRESSIVE...MAYBE 
50-70 KT...AND INCREASE FARTHER N AS IT MERGES WITH A STRONGER 
JET STREAK NEAR THE UPPER LOW. ABUNDANT HIGH LEVEL MOISTURE 
EXTENDS UP TO 700 NM SE OF THE JET...CIRCLING AROUND AN UPPER 
HIGH CENTERED NEAR 13N106W. MODERATE/STRONG TRADES LIE N OF THE 
ITCZ W OF 120W AND ONE SIGNIFICANT CONVECTIVE CLUSTER IS ALONG 
THE ITCZ BETWEEN 126W-130W. FARTHER E...AN UPPER LEVEL CYCLONIC 
SHEAR AXIS EXTENDS FROM HONDURAS SW TO 5N95W WITH DRY N/NE FLOW 
PLUNGING FROM THE GULF OF MEXICO SWD INTO THE PACIFIC...AND 
MOIST AIR CIRCULATING AROUND AN UPPER RIDGE AXIS FROM COLOMBIA 
TO COSTA RICA AND NICARAGUA. ASIDE FROM ITCZ CONVECTION SW OF 
COSTA RICA...OTHER SCATTERED SHOWERS/TSTMS HAVE FORMED IN AN 
AREA OF LOW-LEVEL CONVERGENCE WITHIN 60 NM OF A LINE FROM 
BUENAVENTURA COLOMBIA TO 5N84W.

$$
BERG