000
AXPZ20 KNHC 310304
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL                           
0405 UTC WED JUL 31 2013

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 
0300 UTC.

...SPECIAL FEATURE...                                            
TROPICAL STORM GIL AT 12.9N 117.0W WITH MAXIMUM SUSTAINED WINDS 
OF 40 GUST TO 50 KT AND MOVING W-NW AT 14 KT.  GIL EXPECTED TO 
SLOWLY INTENSIFY AS IT MOVES UNDER VERY FAVORABLE UPPER LEVEL 
CONDITIONS AND WARM SEA SURFACE TEMPERATURES. NUMEROUS MODERATE 
AND SCATTERED STRONG CONVECTION 150 NM NE QUADRANT AND WITHIN 75 
NM ELSEWHERE NOTED AT PRESENT. SEE LATEST NHC FORECAST/ ADVISORY 
UNDER AWIPS/WMO HEADERS MIATCMEP2/WTNT24 KNHC FOR MORE DETAILS.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...           
MONSOON TROUGH AXIS EXTENDS FROM 10N86W TO 09N94W TO 12N103W TO
10N110W. ITCZ AXIS FROM 11N120W TO 109N130W TO 10N140W.
SCATTERED MODERATE ISOLATED STRONG CONVECTION WITHIN 90 NM S OF
AXIS FROM 90W TO 100W AND WITHIN 90 NM OF AXIS FROM 124W TO 126W.

...DISCUSSION...       
VERY LARGE UPPER LEVEL ANTICYCLONE OVER W TEXAS MAINTAINS STEADY
EASTERLY FLOW N OF 20N E OF 120W.  WEAK PERTURBATION IN ITS SW
CORNER INTERRUPS FLOW AND ALLOWS DIMINISHED FLOW TO ENHANCE 
DEVELOPMENT OF NOW TROPICAL STORM GIL.  WELL DEFINED CYCLONE
ALOFT AT 14N102W ALSO DIMINISHES WINDS OVER WEAK 1011 MB LOW 
PRES AT 12N106W BUT OTHERWISE ENVIRONMENT DOES NOT FAVOR ITS
INTENSIFICATION...VERY POSSIBLY DUE TO ITS NEARNESS TO T.S. GIL. 

HIGH PRES CENTER 1027 MB 34N142W PROVIDES STEADY FRESH NE TRADES
WITH SEAS REACHING TO 8 FT FROM 13N TO 19N W OF 136W WITH LITTLE
CHANGE THROUGH FORECAST PERIOD. 
 
$$
WALLY BARNES