000
AXPZ20 KNHC 050404
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC FRI OCT 05 2007

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

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0315 UTC.
  
...TROPICAL WAVE...
TROPICAL WAVE ALONG 111W N OF 5N MOVING W 13 KT. SCATTERED 
MODERATE CONVECTION NOTED WITHIN 120 NM OF THE WAVE AXIS FROM 
10N TO 13N.

...ITCZ...
INTERTROPICAL CONVERGENCE ZONE...AXIS ALONG 6N77W 6N84W 12N110W 
9N130W 11N140W. SCATTERED MODERATE CONVECTION WITHIN 120 NM OF 
8N85W. SCATTERED MODERATE ISOLATED STRONG CONVECTION NOTED FROM 
9N TO 15N BETWEEN 100W AND 116W. 

...DISCUSSION...
A STATIONARY UPPER TROUGH DOMINATES THE DISCUSSION AREA W OF A 
LINE FROM 32N116W 21N140W. A SECOND REINFORCING SHORT WAVE IS 
RACING S...CURRENTLY ALONG 33N120W 30N140W. THE UPPER LEVELS ARE 
DRY N OF 17N W OF 112W AND S OF 15N W OF 120W...AND IS 
EFFECTIVELY SUPPRESSING ITCZ CONVECTION W OF 118W. AT THE LOW 
LEVELS A VERY DRY COLD FRONT IS LOSING IDENTITY FROM 31N118W 
29N128W AND A RIDGE IS BUILDING ALONG 30N135W TO 17N114W. A 
SURGE OF NLY 8 FT SEAS ARE OBSERVED BEHIND THE INITIAL FRONT. 
THE SECONDARY DRY SURGE WILL INCREASE SURFACE WINDS TO 20 KT AND 
BUILD SEAS TO 9 FT INITIALLY...SPREADING S TO 17N IN 48 
HOURS...WITH SEAS BUILDING TO 8 TO 12 FT ALONG 30N IN 48 HOURS. 
   
AN UPPER ANTICYCLONE CONTINUES OVER THE OLD MEXICO AND S TEXAS 
BORDER AT 30N100W WITH A RIDGE EXTENDING SW TO 18N117W. 
IMMEDIATELY TO THE E OF THIS UPPER RIDGE...AN UPPER CYCLONE IS 
OVER MEXICO AT 20N98W WITH ITS ENVELOPE OF CYCLONIC FLOW 
SPREADING INTO THE DISCUSSION AREA TO THE N OF 12N BETWEEN 110W 
AND 97W...PROVIDING THE UPPER SUPPORT FOR THE CONVECTION 
DESCRIBED ABOVE.  

OVER THE PORTION AN UPPER RIDGE EXTENDS S ACROSS CENTRAL AMERICA 
OVER THE WATERS N OF 5N BETWEEN 92W AND 78W...AND IS TURN IS 
SUPPORTING THE CONVECTIVE BURST NEAR 8N85W. 
  
$$
NELSON