000
AXPZ20 KNHC 162202
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC MON JUL 16 2012

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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2100 UTC.

...SPECIAL FEATURES... 
TROPICAL STORM FABIO AT 19.3N 120.1W MOVING NW AT 8 KT WITH 
MAXIMUM WIND 60 GUSTS TO 75 KT.  NUMEROUS MODERATE SCATTERED 
STRONG CONVECTION WITHIN 45 NM NW AND 120 NM SE SEMICIRCLES. 
FABIO CONTINUES WEAKENING TO BECOME TROPICAL DEPRESSION TUE 
NIGHT AS IT MOVES INTO REGION OF COOLER WATERS...DRIER AIR MASS 
AND INCREASING VERTICAL SHEAR.  SEE LATEST NHC FORECAST/ADVISORY 
UNDER AWIPS/WMO HEADER MIATCMEP1/WTPZ21 KNHC FOR MORE DETAILS.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...MONSOON 
TROUGH EXTENDS FROM 09N84W TO 10N88W TO 07N110W TO 09N94W TO 
09N102W TO 07N111W TO 08N116W THEN ITCZ 10N120W.  ITCZ RESUMES 
FROM 10N128W TO BEYOND 06N140W.  SCATTERED MODERATE TO STRONG 
CONVECTION WITHIN 180 NM OF AXIS FROM 97W TO 118W.  ISOLATED 
MODERATE CONVECTION WITHIN 150 NM OF AXIS FROM 127W TO 134W. 

...DISCUSSION...
UPPER LEVEL TROUGH EXTEND SW FROM 32N121W TO WELL-DEFINED 
CYCLONE AT 15N135W THEN W TO BEYOND 15N140W.  VERY DRY SUBSIDING 
AIR MASS N OF 13N W OF 121W PREVENTS ANY SIGNIFICANT DEEP 
CONVECTION AND IS EVEN HELPING DRY OUT AND WEAKEN FABIO WITH ITS 
INCREASE IN SW WIND SHEAR.  UPPER LEVEL ANTICYCLONE AT 26N109W 
FORCED E BY TROUGH ALLOWED FABIO A MORE NORTHERLY TRACK.  SECOND 
BROADER ANTICYCLONE NEAR 12N104W INTRODUCES MODERATE DIVERGENCE 
ALOFT AS A FAVORABLE FACTOR IN INCREASING CONVECTION ALONG 
MONSOON TROUGH E OF 115W.  

MONSOON REGION GETS MORE ACTIVE AS FAVORABLE CONDITIONS GEL INTO 
PLACE...BUT NO PRESENT MECHANISM IS AVAILABLE TO PROMPT UPLIFT.  
SO NO SIGNIFICANT SYSTEM IS EXPECTED TO THREATEN E PAC AT THIS 
TIME NOR FOR THE NEXT TWO DAYS. 

WEAK RIDGE EXTENDS SE FROM SUBTROPICAL HIGH WELL N OF FORECAST 
AREA TO 25N120W JUST N OF FABIO.  FRESH N-NE WINDS REACH 
NORTHERN WATERS W OF 130W.  PRES GRADIENT RELAXES AS FABIO 
WEAKENS NEXT TWO DAYS SO WINDS DIMINISH BY WED. 

$$
WALLY BARNES