000
AXPZ20 KNHC 180948
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC MON OCT 18 2010

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

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0900 UTC.

...ITCZ...
AXIS FROM 09N84W TO 07N94W TO 10N120W TO 09N128W TO 10N134W.  
ISOLATED MODERATE CONVECTION WITHIN 60 NM OF AXIS FROM 94W TO 
100W.  

...DISCUSSION...
UPPER LEVEL TROUGH EXTENDS FROM CENTRAL TEXAS ACROSS MEXICO TO  
15N115W 00N124W. LARGE UPSTREAM ANTICYCLONE HELP EXPAND MODERATE 
TO STRONG SUBSIDING AIR MASS THAT KEEPS MOST OF BASIN DRY FROM 
100W TO 130W S OF 25N.  ANTICYCLONE ADVECTS PLENTY OF TROPICAL 
MOISTURE NE TO NW MEXICO WHERE WEAK SURFACE TROUGH PROMPTS 
ACTIVE TSTMS OVER SRN ARIZONA AND NEW MEXICO.    

DOWNSTREAM FROM UPPER LEVEL TROUGH...SECOND ANTICYCLONE OVER NW 
CARIBBEAN SEA HAS RIDGE EXTEND ACROSS CENTRAL AMERICA INTO E PAC 
TO 08N102W.  GOOD UPPER LEVEL DIVERGENCE ENHANCING CONVECTION 
OVER SURFACE LOW PRES SYSTEM NEAR NICARAGUA E COAST.  RIDGE ALSO 
HELPS IN ADVECTING PLENTY OF TROPICAL MOISTURE E OF 100W 
ALLOWING ITCZ TO BECOME ACTIVE FROM 94W-100W. 

ELSEWHERE AT THE SURFACE...
WEAK TROUGH ALONG 135W FROM 10N TO 16N WITH FRESH NE WINDS AND 
SEAS TO 8 FT EXPECTED TO MOVE W OF 140W WITHIN 24-36 HRS.
  
$$
WALLY BARNES