000
AXPZ20 KNHC 161503
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC MON AUG 16 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 
1430 UTC.

...TROPICAL WAVES...

A TROPICAL WAVE IS N OF 09N ALONG 100W MOVING W TO NW AT 10 KT. 
NO SIGNIFICANT CONVECTION IS NOTED WITH THE WAVE.

A TROPICAL WAVE THAT WAS IN THE GULF OF PANAMA HAS SHIFTED NNW 
TO INLAND OVER WESTERN PANAMA. ANY ASSOCIATED CONVECTION IS NE 
OF THE AREA IN THE CARIBBEAN SEA.

...ITCZ...

THE AXIS IS ANALYZED ALONG 07N81W TO 09N87W TO 09N93W TO 11N98W 
THEN 12N105W TO 10N120W TO 09N127W THEN 08N131W TO 07N135W TO 
09N140W. SCATTERED MODERATE CONVECTION IS WITHIN 90 NM S OF THE 
AXIS BETWEEN 82W AND 90W AND ALSO WITHIN 60 NM EITHER SIDE OF 
THE AXIS BETWEEN 95W AND 97W.

...DISCUSSION...

A SHARP INVERTED UPPER LEVEL TROUGH LIES ALONG 105W N OF 14N. 
THIS TROUGH IS EMBEDDED IN UPPER LEVEL RIDGING STEMMING 
PRIMARILY FROM AN ANTICYCLONE WELL NE OF THE AREA NEAR 30N95W. 
AN UPPER RIDGE EXTENDS SOUTHWARD TO NEAR 18N101W. UPPER LEVEL 
DIFFLUENCE ASSOCIATED WITH THIS RIDGE AXIS IS ENHANCING THE 
CONVECTION OVER MEXICO AND IN THE GULF OF TEHUANTEPEC N OF 13N 
BETWEEN 93W AND 98W. AN UPPER LEVEL ANTICYCLONE IS CENTERED NEAR 
20N125W WITH ANOTHER SMALLER ANTICYCLONE JUST W OF CENTRAL BAJA 
CALIFORNIA NEAR 27N116W. AN UPPER LOW IS POSITIONED BETWEEN 
THESE TWO ANTICYCLONES NEAR 25N125W. THIS LOW IS SIPHONING SOME 
MID AND UPPER LEVEL MOISTURE FROM FAR NW MEXICO AND S CALIFORNIA.

AT THE SURFACE...A 1023 MB HIGH IS CENTERED JUST NW OF THE 
DISCUSSION AREA NEAR 33N145W WITH A SURFACE RIDGE EXTENDING FROM 
THE HIGH INTO THE AREA NEAR 31N140W TO 24N127W TO 22N115W. SE TO 
S WINDS TO 20 KT ARE OCCURRING IN THE GULF OF CALIFORNIA N OF 
29N DUE TO A TIGHT PRES GRADIENT BETWEEN THE RIDGE W OF BAJA 
CALIFORNIA AND TROUGHING IN THE SW U.S. AND NW MEXICO. THESE 
WINDS ARE EXPECTED TO DIMINISH TO LESS THAN 20 KT BY THIS 
EVENING AS THE PRES GRADIENT WEAKENS.

A 1008 MB AREA OF LOW PRES IS POSITIONED NEAR 20N109W AND IS 
NEARLY STATIONARY. SCATTERED MODERATE CONVECTION IS FROM 18N TO 
21N BETWEEN 107W AND 114W. WINDS OF 20 TO 25 KT ARE OCCURRING 
WITHIN 180 NM OF THE LOW CENTER IN THE NE QUADRANT WITH 20 KT 
WINDS WITHIN 90 NM OF THE LOW CENTER IN THE REMAINING QUADRANTS. 
MODEL GUIDANCE MOVES THE LOW OFF TO THE NW DURING THE NEXT FEW 
DAYS AND IT MAY DISSIPATE TUE NIGHT WITH WINDS DIMINISHING TO 
LESS THAN 20 KT BY 00 UTC WED AS 20 TO 30 KT EASTERLY SHEAR 
CONTINUES TO IMPACT THE LOW.

A SURFACE TROUGH IS EMBEDDED IN THE ITCZ OVER THE W WATERS 
EXTENDING ALONG 129W FROM 07N TO 14N. SCATTERED SHOWERS ARE 
OCCURRING WITHIN 300 NM EITHER SIDE OF THE TROUGH AXIS.

CROSS EQUATORIAL SW SWELL WITH PERIODS OF 17 TO 19 SECONDS IS 
EXPECTED TO REACH 8 TO 9 FT OVER THE S CENTRAL WATERS BY EARLY 
TUE MORNING AND WILL EXPAND N TO NE TO 10N BETWEEN 92W AND 120W 
BY EARLY WED MORNING.

$$
LEWITSKY