000
AXPZ20 KNHC 212159
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC MON JAN 21 2008

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

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC.
 
...ITCZ...
ITCZ AXIS ALONG 8N77W 4N92W 7N140W. NO SIGNIFICANT CONVECTION.

...DISCUSSION...
A LONGWAVE TROUGH THAT DISSECTS N AMERICA FROM NE CANADA TO 
OREGON HAS A SHORTWAVE TROUGH ROTATING TROUGH THE PATTERN AND 
EXTENDING S INTO THE DISCUSSION AREA ALONG 32N125W 24N140W WITH 
DRY UPPER AIR WITHIN 120 NM EITHER SIDE LINE 32N105W 32N120W 
26N140W. AN UPPER LEVEL ANTICYCLONE IS S OF THE AREA NEAR 
14S130W WITH AN UPPER RIDGE EXTENDING N ACROSS THE EQUATOR TO A 
CREST ALONG 19N140W 30N120W 30N100W 24N100W. DENSE UPPER 
MOISTURE IS NOTED UNDER THE RIDGE AND SPREADING NE TOWARDS 
NORTHERN OLD MEXICO.  

A SECOND SHORTWAVE TROUGH IS NOTED ALONG THE EASTERN CONUS AND 
EXTENDS S INTO THE AREA ALONG 32N83W TO A BASE NEAR THE 
GALAPAGOS ISLANDS. THE TROUGH IS ACCOMPANIED BY VERY DRY AIR 
DOMINATING THE REGION S OF 22N E OF 105W AND IS SUPPRESSING 
CONVECTION.
 
THE PRES GRADIENT WILL CONTINUE TO SUPPORT WINDS JUST BELOW GALE 
IN AND JUST DOWNSTREAM OF BOTH THE GULF OF TEHUANTEPEC AND THE 
GULF OF PAPAGAYO FOR AT LEAST ANOTHER 48 HOURS. 

$$
NELSON