000
AXPZ20 KNHC 282151
TWDEP 

TROPICAL WEATHER DISCUSSION                                      
NWS NATIONAL HURRICANE CENTER MIAMI FL                           
2205 UTC FRI JUN 28 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2115 UTC.

...SPECIAL FEATURE...
LOW PRES CENTER AT 11N104W 1008 MB BECOMING BETTER ORGANIZED 
WITH TROPIPCAL CHARACTERISTIC NOTED AND UNDER FAVORABLE ENVIRON
ALOFT AND A LOWER LEVELS.  WITH SEA SURFACE TEMPERATURES NEAR 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 70 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 WITHIN 300 NM N OF CENTER
AND 210 NM S OF IT.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... 
MONSOON TROUGH AXIS EXTENDS FROM 10N85W TO 12N93W TO 1008 MB LOW
PRES AT 11N104W TO 15N114W THEN RESUMES FROM 12N125W TO 07N140W.
SCATTERED MODERATE TO STRONG CONVECTION WITHIN 210 NM S AND 300
NM N OF AXIS E OF 110W.  

...DISCUSSION... 
UPPER LEVEL ANTICYCLONE AT 30N125W HAS RIDGE EXTENDING SW TO 
20N140W WITH VERY DRY SUBSIDING AIR MASS N OF 12N W OF 120W.  
ANTICYCLONE FORCED NE BY UPPER LEVEL LONG WAVE TROUGH APPROACHING
FROM THE NW ALLOWING DEVELOPING ANTICYCLONE TO MOVE OVER LOW
PRES CENTER MENTIONED IN PARAGRAPH ABOVE.  THIS ANTICYCLONE
STRENGTHNS 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 16N109W.  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 SWIRL NEAR
22N128W.  LOW PRES FORECAST TO DISSIPATE SAT.
 
$$ 
WALLY BARNES