000
AXPZ20 KNHC 250247
TWDEP 

TROPICAL WEATHER DISCUSSION                                      
NWS NATIONAL HURRICANE CENTER MIAMI FL                           
0405 UTC TUE JUN 25 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 FEATURES...

TROPICAL STORM COSME AT 15.9N 107.9W 995 MB AT 0300 UTC JUN 25 
MOVING NW OR 305 DEGREES AT 12 KT. MAXIMUM SUSTAINED WINDS ARE 
55 KT WITH GUSTS TO 65 KT. NUMEROUS MODERATE TO STRONG 
CONVECTION WITHIN 120 NM IN THE SE SEMICIRCLE...AND WITHIN 90 NM 
N QUADRANT FROM THE CENTER. COSME IS FORECAST TO BECOME A 
HURRICANE TUE THEN WEAKEN TO A TROPICAL STORM ON THU AS IT 
CONTINUES NW OVER COOLER WATERS. SEE THE LATEST 
FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP3/WTNT23 KNHC 
FOR MORE DETAILS.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... 
           
MONSOON TROUGH 09N79W ACROSS WESTERN PANAMA AND SOUTHERN COSTA 
RICA TO 13N100W...THEN RESUMES FROM 13N112W TO 09N131W. ITCZ 
EXTENDS FROM 09N131W TO 07N140W. SCATTERED MODERATE CONVECTION 
WITHIN 180 NM S OF MONSOON TROUGH AXIS BETWEEN 80W AND 84W. 
SCATTERED MODERATE WITHIN 120 NM S OF AXIS BETWEEN 112W AND 
115W...AND 119W AND 123W. SCATTERED MODERATE ISOLATED STRONG 
WITHIN 60 NM N OF ITCZ BETWEEN 136W AND 139W.  
 
...DISCUSSION... 

SCATTEROMETER DATA FROM 18 UTC AND REPORTS FROM TOGA-TAO BUOY 
43001 INDICATED A SURGE OF 25 TO 30 KT SW FLOW INTO 
COSME...ACCOUNTING FOR A LARGE FLARE UP OF CONVECTION ON THE 
SOUTHERN PERIPHERY OF THE STORM. THIS HAS SINCE DIMINISHED ON 
SATELLITE IMAGERY WITH TOPS WARMING CONSIDERABLE. DEVELOPING 
CONVECTION IS NOTED AROUND THE CENTER OF THE CYCLONE...WITHIN 
120 NM IN THE SE SEMICIRCLE...AND STARTING TO WRAP INTO THE N TO 
NW QUADRANTS AS WELL...REPRESENTING A STRONG TROPICAL STORM. 

FARTHER EAST...AN AREA OF CONVECTION HAS MOVED FROM THE BAY OF 
PANAMA ACROSS WESTERN PANAMA AND ITS ADJACENT OFFSHORE WATERS 
ALONG THE MONSOON TROUGH. THIS HAS BEEN AN ACTIVE AREA FOR 
CONVECTION OVER THE PAST SEVERAL DAYS...ENHANCED IN PART BY AN 
UPPER CYCLONE CENTERED OVER THE NW CARIBBEAN WITH A TROUGH 
EXTENDING INTO THE SW CARIBBEAN.

A SURFACE RIDGE EXTENDS FROM 26N140W TO 26N120W TO SOUTHERN BAJA 
PENINSULA. THIS IS MAINTAINING GENERALLY LIGHT WINDS N OF 
20N...AND 10 TO 15 KT TRADES S OF 20N W OF 120W. SEAS ARE 
RUNNING 4 TO 5 FT OVERALL N OF 10N W OF 120W. MEANWHILE CROSS 
EQUATORIAL SW SWELL...RESULTING IN COMBINED SEAS TO 10 
FT...CONTINUES TO PROPAGATE NE TO PASS 10N BETWEEN 100W-130W 
MIXING WITH THE SWELLS GENERATED BY TROPICAL CYCLONE COSME 
BEGINNING TODAY. THE SWELL COMPONENT REACHING THE COAST OF 
MEXICO BETWEEN ACAPULCO AND CABO CORRIENTES...AND WILL BE 
REINFORCED BY THE CYCLONE WITH THE COMBINED S SWELL MOVING INTO 
THE SOUTHERN GULF OF CALIFORNIA ON TUE NIGHT...AND PROPAGATING N 
ALONG THE WESTERN SHORE OF THE BAJA PENINSULA ON WED REACHING 
ALONG 30N ON WED NIGHT. THESE SWELLS ARE LIKELY TO CAUSE LIFE-
THREATENING SURF AND RIP CURRENT CONDITIONS.
 
$$ 
CHRISTENSEN