000
AXPZ20 KNHC 290246
TWDEP 

TROPICAL WEATHER DISCUSSION                                      
NWS NATIONAL HURRICANE CENTER MIAMI FL                           
0405 UTC SAT JUN 29 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 
0315 UTC.

...SPECIAL FEATURE...
LOW PRES CENTER AT 11N105W 1008 MB BECOMING BETTER ORGANIZED 
WITH CYCLONIC TURNING NOTED AND UNDER FAVORABLE ENVIRONMENT ALOFT
AND AT LOWER LEVELS.  WITH SEA SURFACE TEMPERATURES ABOVE 28 DEG
...SURROUNDED BY WARM MOIST AIR MASS...VIGOROUS UPPER LEVEL
SHORTWAVE JUST TO ITS NW AND DEVELOPING ANTICYCLONE ALOFT TO 
PROVIDE GOOD OUTFLOW...NHC BOOSTED ITS PROBABILITY OF BECOMING A
TROPICAL CYCLONE DURING THE NEXT 48 HRS TO 80 PERCENT.  SIMILARLY
...MODEL GUIDANCE INTENSIFY SYSTEM TO TROPICAL CYCLONE AND TAKE
IT N CLOSER TO COAST OF MEXICO THEN RUN NW PARALLEL TO THE COAST
BEFORE TURNING W ALONG 20N AWAY FROM THE COAST.  PRESENTLY...
SCATTERED MODERATE TO STRONG CONVECTION...SOME IN CURVING BANDS
...ARE WITHIN 210 NM OF CENTER.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... 
MONSOON TROUGH AXIS EXTENDS FROM 11N86W TO 10N91W TO 12N98W TO
1008 MB LOW PRES AT 11N105W TO 12N110W THEN RESUMES FROM 12N127W
TO 08N135W TO BEYOND 07N140W.  SCATTERED MODERATE TO STRONG 
CONVECTION WITHIN 150 NM OF AXIS E OF 108W.

...DISCUSSION... 
UPPER LEVEL ANTICYCLONE AT 29N126W HAS RIDGE EXTENDING SW TO 
20N140W WITH VERY DRY SUBSIDING AIR MASS N OF 12N W OF 121W.  
ANTICYCLONE IS FORCED NE BY UPPER LEVEL LONG WAVE TROUGH 
APPROACHING FROM THE NW AND ALLOWS DEVELOPING ANTICYCLONE TO
MOVE OVER LOW PRES CENTER MENTIONED IN SPECIAL FEATURES.  THIS
ANTICYCLONE STRENGTHENS AND PREVENTS LONG WAVE TROUGH TO MOVE
FURTHER E INTO BASIN.  WEAK COLD FRONT ASSOCIATED WITH LONGWAVE
TROUGH STALLS AND DISSIPATES BARELY ENTERING FAR NW CORNER OF
E PAC. 

UPPER LEVEL CYCLONE OVER SW GULF OF MEXICO HAS TROUGH EXTENDING 
SW TO NEAR 14N110W.  TROUGH SUSTAINS DEEP LAYER MOISTURE AND 
PROVIDES DIFFLUENCE ALOFT OVER LOW PRES FEATURE. 

...ELSEWHERE AT LOWER LEVELS...
SURFACE HIGH 1021 MB 34N130W BULGES A RIDGE BEHIND REMNANT LOW
PRES...PREVIOUSLY COSME...NOW JUST A CONVECTION-LESS 1006 MB 
SWIRL NEAR 23N130W.  LOW PRES FORECAST TO DISSIPATE SAT.
 
$$ 
WALLY BARNES