000
AXPZ20 KNHC 210310
TWDEP 

TROPICAL WEATHER DISCUSSION   
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC FRI APR 21 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 
0245 UTC.

...ITCZ...
ITCZ AXIS IS CENTERED ALONG 8N83W 7N95W 8N110W 5N125W 6N140. 
SCATTERED MODERATE CONVECTION WITHIN 75 NM EITHER SIDE OF AXIS 
FROM 125W TO 132W. 

...DISCUSSION...

N OF 20N...
A TROUGH-RIDGE-TROUGH CONFIGURATION PREVAILS IN THE MID/UPPER 
LEVELS WITH A SHARP TROUGH OVER THE W PORTION OF THE AREA FROM 
32N128W TO 20N140W...A RIDGE E OF 120W INTO W PORTIONS OF MEXICO 
...AND A TROUGH FROM NE MEXICO NWD INTO THE CENTRAL UNITED 
STATES. SIGNIFICANT CLOUDS/CONVECTION REMAIN ABSENT IN THIS 
PATTERN ESPECIALLY OVER THE FAR NW PART AND W MEXICO WHERE 
CONFLUENT FLOW IN THE UPPER LEVELS IS CREATING DRY/STABLE 
CONDITIONS.  ISOLATED SHOWERS AND TSTMS ARE OBSERVED OVER E 
MEXICO PRIMARILY NEAR THE E SLOPES OF THE SIERRA MADRE ORIENTAL 
MOUNTAINS. ELSEWHERE...A FEW HIGH CLOUDS ACCOMPANY A 70-110 KT 
JET STREAM ALONG 18N140W 18N130W THEN NEWD INTO S CALIFORNIA AND 
N BAJA.  AT THE SURFACE...WEAKENING COLD FRONT LIES OVER THE NW 
PORTION OF THE AREA FROM 32N133W TO 28N140W WHERE IT DEGENERATES 
INTO A SHEAR AXIS.  LACKING APPRECIABLE DYNAMICS AND 
MOISTURE...THE FRONT IS NOTICEABLY ABSENT OF BOTH SHOWERS AND 
SIGNIFICANT CLOUDS. HOWEVER...THE FRONT IS ACCOMPANIED BY NW 
SWELLS TO 12 FT WHICH WILL SPREAD EWD OVER THE N PORTION OF THE 
DISCUSSION AREA TO 130W OVER THE NEXT 24 HRS. THE FRONT IS 
EXPECTED TO CONTINUE WEAKENING OVER THE NEXT 24 HRS AS IS PUSHES 
EWD FURTHER WEAKENING THE PACIFIC SUBTROPICAL RIDGE. 

S OF 20N...
BROAD MIDDLE TO UPPER LEVEL RIDGE EXTENDS FROM COLOMBIA NW ALONG 
CENTRAL AMERICA INTO S MEXICO.  VERY DRY AIR PREVAILS IN THE MID 
AND UPPER LEVELS E OF 110W RESULTING IN LITTLE OR NO SIGNIFICANT 
ITCZ CONVECTION.  FARTHER W...DIFFLUENT FLOW ALOFT NEAR THE BASE 
OF THE AFOREMENTIONED UPPER TROUGH...N OF 20N W OF 120W...IS 
AIDING WIDELY SCATTERED TO LOCALLY SCATTERED ITCZ CONVECTION W 
OF 120W. 

$$
RHOME