000
AXPZ20 KNHC 272149
TWDEP 

TROPICAL WEATHER DISCUSSION                                     
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
2205 UTC SUN SEP 27 2015

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 
2145 UTC.               

...SPECIAL FEATURE...

TROPICAL STORM MARTY IS CENTERED AT 15.1N 102.9W...OR ABOUT 235 
MILES W-SW OF ACAPULCO MEXICO...AT 2100 UTC WITH AN ESTIMATED 
PRESSURE OF 997 MB. MARTY IS MOVING N...OR 005 DEG AT 03 KT. 
MAXIMUM SUSTAINED WINDS ARE 50 KT WITH GUSTS TO 60 KT. CURRENTLY 
NUMEROUS MODERATE TO STRONG CONVECTION IS OBSERVED WITHIN 120 NM 
OVER THE NE QUADRANT. SCATTERED MODERATE ISOLATED STRONG 
CONVECTION IS OBSERVED ELSEWHERE WITHIN 240 NM EITHER SIDE OF A 
LINE FROM 17N100W TO 11N107W. A SLOW TURN TOWARDS THE NE IS 
EXPECTED TONIGHT. THE STORM IS FORECAST TO FURTHER STRENGTHEN  
TONIGHT INTO MON...THEN INCREASING WIND SHEAR WILL RESULT IN A 
WEAKENING TREND BEGINNING ON MON NIGHT. HEAVY RAINFALL IS 
EXPECTED TO PRODUCE LIFE-THREATENING FLASH FLOODS AND MUDSLIDES 
ACROSS THE SOUTHERN STATE OF GUERRERO MEXICO. LARGE SWELLS WILL 
REACH THE PACIFIC COAST OF MEXICO BETWEEN 100-105W THROUGH THE 
MIDDLE OF THE WEEK RESULTING IN DANGEROUS SURF AND RIP CURRENTS. 
INTERESTS ARE ENCOURAGED TO REFER TO THE LATEST NHC 
FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP2/WTPZ22 KNHC 
FOR UPDATED DETAILS. 
  
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...            

THE MONSOON TROUGH IS ANALYZED BETWEEN 10-11N FROM THE CARIBBEAN 
COAST OF COLOMBIA AT 11N75W TO THE PACIFIC COAST OF COSTA RICA 
AT 10N85W THEN TURNS NW TO 13N97W WHERE IT LOSES IDENTITY IN THE 
BROAD CYCLONIC CIRCULATION ASSOCIATED WITH TROPICAL STORM MARTY. 
SCATTEROMETER WINDS SUGGEST THAT THE MONSOON TROUGH RESUMES SW 
OF MARTY NEAR 13N113W...AND CONTINUES SW THROUGH AN EMBEDDED 1009 
MB LOW PRESSURE AT 09N122W TO 08N127W...THEN TURNS NW TO 
13N135W....THEN SW TO BEYOND 11N140W. SCATTERED MODERATE 
ISOLATED STRONG CONVECTION IS OBSERVED WELL S OF THE MONSOON 
TROUGH WITHIN 120 NM OF 08N91W...AND WITHIN 120 NM EITHER SIDE 
OF A LINE FROM 11N107W TO 06N128W TO 13N135W TO 10N140W. 

THE SURFACE LOW AT 09N122W WILL MOVE E TO A POSITION NEAR 
11N119W ON MON AND NEAR 11N116W ON TUE. SOUTHERLY FLOW SE OF THE 
LOW IS AT 20-25 KT WITHIN 240 NM SE OF A LINE FROM 06N125W TO 
10N110W WITH 7-10 FT SEAS. CROSS EQUATORIAL SOUTHERLY SWELL IS 
MIXING WITH LONG PERIOD NW SWELL...RESULTING IN COMBINED SEAS OF 
7-9 FT...SURROUND THE AREA OF STRONGER SOUTHERLY WINDS TO THE S 
OF 10N BETWEEN 95-120W. 
  
A SURFACE RIDGE EXTENDS SE FROM 32N130W TO 16N115W. A 1011 MB  
SURFACE LOW HAS OCCLUDED NEAR 31N136W AND IS TRAILING A WEAK 
COLD FRONT SW ACROSS THE DISCUSSION AREA FROM 30N133W TO BEYOND 
22N140W. THIS WEAK COLD FRONT WILL CONTINUE E TO A POSITION FROM 
32N129W TO 27N132W TO 20N140W ON MON AS A SECOND COLD FRONT 
MOVES INTO THE DISCUSSION AREA FROM 32N135W TO 26N140W. 
NORTHERLY WINDS WILL INCREASE TO 20-25 KT N OF 30N W OF THE   
SECOND FRONT ON SUN...WITH NW-N 15-20 KT WINDS EXPECTED S OF 30N 
W OF THE FRONT. COMBINED SEAS WILL INCREASE TO 8-12 FT N OF 30N 
AND 7-10 FT S OF 30N PRIMARILY IN MIXED N AND S SWELL. THE FIRST 
FRONT WILL WEAKEN TO A FRONTAL TROUGH FROM 32N128W TO 20N140W ON 
TUE AS THE SECOND FRONT BEGINS TO WEAKEN FROM 30N134W TO 
26N135W. BY THEN ASSOCIATED WINDS WILL HAVE DIMINISHED TO 15-20 
KT AND SEAS SUBSIDED TO 5-7 FT.
    
$$
NELSON