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Eastern Pacific Tropical Weather Discussion (Text)

000
AXPZ20 KNHC 181519
TWDEP 

TROPICAL WEATHER DISCUSSION                                      
NWS NATIONAL HURRICANE CENTER MIAMI FL                           
1605 UTC TUE JUN 18 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...            
MONSOON TROUGH 9N84W TO 7N95W TO 1008 MB LOW AT 10N105W TO 
11N111W. ITCZ 11N111W TO 12N120W TO 8N140W. SCATTERED MODERATE 
TO STRONG CONVECTION WITHIN 200 NM S OF AXIS FROM 84W-87W AND 
WITHIN 160 NM N OF AXIS FROM 105W-107W. SCATTERED MODERATE 
CONVECTION WITHIN 90 NM N OF AXIS FROM 115W-125W 

...DISCUSSION...                                                
BROAD UPPER LEVEL TROUGH N OF 30N W OF 125W. A BROAD UPPER LEVEL 
RIDGE IS S OF THE TROUGH AND COVERS MUCH OF THE DISCUSSION AREA 
THE RIDGE AXIS EXTENDS FROM AN ANTICYCLONIC CIRCULATION CENTERED 
NEAR 16N137W TO THE SOUTHERN TIP OF THE BAJA PENINSULA THEN INTO 
MEXICO. STRONG SUBSIDENCE WITH DRY STABLE AIR AT THE MIDDLE AND 
UPPER LEVELS IS ACROSS THE AREA N OF 15N W OF 110W. AN UPPER 
LEVEL CYCLONIC CIRCULATION CENTERED NEAR 14N99W WITH A TOUGH 
EXTENDING NORTHWARD INTO SOUTHERN MEXICO. DIFFULENT FLOW BETWEEN 
THE CYCLONIC CIRCULATION AND AN ANTICYCLONIC CIRCULATION OVER 
THE NW CARIBBEAN IS ENHANCING CONVECTION ALONG THE COAST OF 
COSTA RICA AND PANAMA.

SURFACE RIDGE IS N OF 15N W OF 115W. ALONG THE SOUTHERN 
PERIPHERY OF THE RIDGE THE GRADIENT IS TIGHT ENOUGH TO SUPPORT 
ELY 20-25 KT WINDS FROM 10N-15N W OF 135W...WITH SEAS TO 10 FT. 
ELSEWHERE FROM 10-20N W OF 125W WINDS ARE 20 KT OR LESS HOWEVER 
SEAS ARE TO 9 FT IN NE SWELL. NLY SWELLS ARE N OF 29N BETWEEN 
119W AND 122W ARE FORECAST TO BUILD 8-10 FT N OF 26N BETWEEN 
116W-122W WED AND EXPAND TO N OF 25N BETWEEN 116W-120W THU. 

$$ 
DGS