000
AXPZ20 KNHC 300248
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC MON AUG 30 2010

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W.

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0130 UTC.

...ITCZ...

INTERTROPICAL CONVERGENCE ZONE AXIS ANALYZED FROM 12N86W TO 
13N95W TO 12N120W TO 12N128W TO 11N140W. SCATTERED MODERATE TO 
STRONG CONVECTION IS WITHIN 150 NM S OF THE ITCZ AXIS BETWEEN 
104W AND 116W. SCATTERED MODERATE CONVECTION IS WITHIN 90 NM S 
OF THE ITCZ AXIS E OF 89W.

...DISCUSSION...

ALOFT...A DEEP TROUGH ALONG THE WEST COAST OF THE U.S. EXTENDS 
ITS INFLUENCE AS FAR SOUTH AS 24N ALONG 120W...CREATING A 
WEAKNESS IN THE SUBTROPICAL RIDGE NEAR 22N122W. THE RIDGE 
EXTENDS W FROM AN UPPER LEVEL ANTICYCLONE CENTERED OVER MEXICO 
NEAR 24N101W TO BEYOND 23N140W. DIFFLUENT ELY FLOW PREVAILS NEAR 
THE MEXICAN COAST BETWEEN THIS ANTICYCLONE AND AN INVERTED UPPER 
TROUGH FROM NEAR 20N90W TO 10N93W. SCATTERED MODERATE CONVECTION 
WITHIN 75 NM OF THE COAST FROM 16N TO 22N...BETWEEN 91W AND 
94W...AND BETWEEN 82W AND 84W IS BEING ENHANCED BY THIS UPPER 
LEVEL DIFFLUENCE. THE STRONGEST INLAND CONVECTION LIES NEAR THE 
UPPER RIDGE AXIS OVER THE SIERRA MADRE OCCIDENTAL MOUNTAINS AND 
TO THE COAST FROM 22N TO 26N.

SURFACE...A 1730 UTC ASCAT PASS OVER REMNANT LOW OF FRANK SHOWED 
AN ELONGATED LOW LEVEL CIRCULATION WITH WINDS TO 25 KT IN THE W 
QUADRANT. WINDS WILL CONTINUE TO DECREASE TONIGHT AS FRANK 
DISSIPATES BY MORNING. SHIP A8RH4 NEAR 26N118W AND AN UNKNOWN 
SHIP NEAR 25N114W AT 0000 UTC BOTH REPORTED 20 KT WINDS AND SEAS 
IN THE 8-9 FT RANGE. THESE WINDS ARE DRIVEN BY THE PRES GRADIENT 
BETWEEN THE SUBTROPICAL RIDGE FROM 27N140W TO 25N115W AND THE 
TROUGHING JUST TO ITS N ASSOCIATED WITH THE DEEP LAYERED TROUGH 
EXTENDING FROM THE SW CONUS INTO N WATERS. THE ASCAT PASS ALSO 
SHOWED MODERATE LOW LEVEL CONVERGENCE FROM NORTHWESTERLY FLOW 
AND 20 TO 25 KT WEST-SOUTHWESTERLY FLOW IN THE REGION FROM 10N 
TO 13N BETWEEN 95W AND 120W. SCATTERED MODERATE TO STRONG 
CONVECTION LIES IN THIS REGION...SPECIFICALLY WITHIN 150 NM S OF 
THE ITCZ AXIS BETWEEN 104W AND 116W. 

MARINE...SURGE OF CROSS-EQUATORIAL LONG PERIOD SWELL IS SWEEPING 
NORTHWARD ACROSS THE FORECAST WATERS E OF 110W. THESE SWELLS 
HAVE REACHED THE COAST OF CENTRAL AMERICA AND SOUTHERN 
MEXICO...WITH PERIODS OF 15 TO 18 SEC. SEAS ARE ONLY EXPECTED TO 
REACH 8 FT IN THE WATERS OFFSHORE OF THE COAST AS FAR N AS 16N 
THROUGH TUE NIGHT.

$$
MUNDELL/SCHAUER