000
AXPZ20 KNHC 151526
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC SUN AUG 15 2010

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

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC.

...TROPICAL WAVE...

A TROPICAL WAVE ALONG 95W N OF 10N. SCATTERED MODERATE WITH 
ISOLATED STRONG CONVECTION LIES WITHIN 120 NM E OF THE WAVE N OF 
12N. SCATTERED MODERATE TO STRONG CONVECTION LIES WITHIN 180 NM 
WEST OF THE WAVE AXIS N OF 10N.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE IS ANALYZED FROM 10N130W TO 
10N140W. NO SIGNIFICANT CONVECTION LIES ALONG THE ITCZ AT THIS 
TIME. 

...DISCUSSION...

AN UPPER LEVEL RIDGE EXTENDS FROM THE SOUTHWESTERN U.S. THROUGH 
THE FAR NORTHERN GULF OF CALIFORNIA SOUTHWESTWARD TO NEAR 
23N140W. SUBSIDENT CONDITIONS CAN BE FOUND NW OF THIS RIDGE AXIS 
AND ARE MARKED BY THE DRY AIR ON WATER VAPOR IMAGERY. A SHARP 
UPPER TROUGH LIES FROM 15N130W TO NORTHERN MEXICO NEAR 30N114W. 
AN ANTICYCLONE LIES S OF THE TROUGH OVER MEXICO NEAR 25N107W AND 
EXTENDS A RIDGE TO 08N123W. AN UPPER LEVEL TROUGH EXTENDS FROM 
EASTERN MEXICO SOUTH TO 12N100W. 

A SURFACE RIDGE LIES ALONG 30N. THE PRESSURE GRADIENT BETWEEN 
THIS RIDGE AND TROUGHING IN THE GULF OF CALIFORNIA CONTINUES TO 
RESULT IN NW TO N WINDS TO 20 KT NEAR THE W COAST OF BAJA 
CALIFORNIA N OF 26N. THIS RIDGE AXIS IS EXPECTED TO MOVE 
SOUTHWESTWARD OVER THE NEXT 24 HOURS...DECREASING THE PRES 
GRADIENT OVER NE WATERS...AND DIMINISHING THE WINDS BELOW 20 KT 
BY MON AFTERNOON. TROUGHING OVER THE SW U.S. WILL DEEPEN TODAY 
AS A COLD FRONT DIVES SOUTH OF THE U.S. FOUR CORNERS. THIS WILL 
INCREASE THE PRES GRADIENT OVER THE NORTHERN GULF OF CALIFORNIA 
AND INCREASE SOUTHERLY WINDS TO 20 KT BY THIS EVENING. 

A 1008 MB LOW IS CENTERED NEAR 17N109W. THIS LOW IS EMBEDDED IN 
THE MONSOON TROUGH THAT EXTENDS FROM 11N120W TO 18N105W. THE SW 
MONSOONAL FLOW IS ADVECTING TROPICAL MOISTURE NORTHEASTWARD ON 
THE EAST SIDE OF THE LOW. FRESH TO STRONG SW WINDS ARE SOUTH OF 
THE LOW AND ARE HELPING KEEP SEAS IN THE 8 TO 11 FT RANGE IN SW 
SWELL. THE LOW IS FORECAST TO SHIFT GRADUALLY NORTHWESTWARD OVER 
THE NEXT FEW DAYS AS THE MONSOON TROUGH AXIS SHIFTS EASTWARD AND 
WINDS AND SEAS BEGIN TO DIMINISH.

$$
AL