000
AXPZ20 KNHC 052147
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC WED OCT 05 2011

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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2100 UTC.
 
...SPECIAL FEATURE...

TWO AREAS OF LOW PRES...WITH POTENTIAL TO DEVELOP INTO TROPICAL 
CYCLONES ARE NOTED ALONG THE MONSOON TROUGH THIS AFTERNOON. THE 
EASTERNMOST IS LOCATED NEAR 10N104W. SHOWER AND THUNDERSTORM 
ACTIVITY ASSOCIATED WITH THIS SYSTEM HAS BECOME A LITTLE BETTER 
ORGANIZED. ENVIRONMENTAL CONDITIONS APPEAR CONDUCIVE FOR 
DEVELOPMENT...AND THIS DISTURBANCE COULD BECOME A TROPICAL 
DEPRESSION DURING THE NEXT DAY OR TWO. 

THE WESTERNMOST IS GETTING BETTER ORGANIZED AND IS CURRENTLY  
SITUATED NEAR 11.5N115W. CONDITIONS APPEAR FAVORABLE FOR 
ADDITIONAL DEVELOPMENT. THIS LOW IS LIKELY TO BECOME A TROPICAL 
DEPRESSION DURING THE NEXT DAY OR TWO AS IT MOVES 
WEST-NORTHWESTWARD AT ABOUT 5-10 KT. 

...ITCZ/MONSOON TROUGH...

MONSOON TROUGH ALONG 10N86W TO LOW PRES 10N104W 1008 MB TO LOW 
PRES 11.5N115W 1009 MB TO 11N120W TO 08N132W. THE ITCZ AXIS 
EXTENDS FROM 08N132W TO 08N140W. SCATTERED MODERATE TO STRONG 
WITHIN 180 NM S OF MONSOON TROUGH AND ALSO WITHIN 90 NM N OF 
MONSOON TROUGH BETWEEN 90W AND 100W. SIMILAR CONVECTION IS 
WITHIN 75 NM N SEMICIRCLE...120 NM SE...AND 240 NM SW QUADRANTS 
OF FIRST LOW. SCATTERED MODERATE TO STRONG WITHIN 180 NM SE AND 
240 NM SW QUADRANTS OF SECOND LOW. ISOLATED TO SCATTERED 
MODERATE FROM 11.5N TO 17N BETWEEN 113W AND 120W. SCATTERED 
MODERATE ISOLATED STRONG FROM 09N TO 12N BETWEEN 10W AND 127W.

...DISCUSSION...

A COLD FRONT IS JUST MOVING INTO THE N WATERS. MODERATE NW WINDS 
AND BUILDING SEAS TO 8 FT IN N SWELL CAN BE FOUND IN THE WAKE OF 
THE FRONT WHICH IS FORECAST TO DISSIPATE IN ABOUT 24 HOURS. NLY 
SWELL BEHIND THE FRONT WILL MERGE WITH SW SWELL RAISING SEAS TO 
8 TO 11 FT MAINLY N OF 27N AND W OF 120W THU AND FRI. AHEAD OF 
THE COLD FRONT...A SMALL AREA OF FRESH W-SW WINDS WILL AFFECT 
THE NORTHERN GULF OF CALIFORNIA ON THU. THEN...WINDS WILL SHIFT 
TO THE NW AND N WITH THE FRONTAL PASSAGE REMAINING AT 20 KT N OF 
29N ON FRI.
 
WINDS ARE ALSO EXPECTED TO INCREASE TO 20 KT N OF 27N AND WITHIN 
120 NM W OF BAJA CALIFORNIA PENINSULA AS PRES GRADIENT TIGHTENS 
BETWEEN HIGH PRES DOMINATING THE N WATERS AND LOWER PRES OVER NW 
MEXICO.

A HIGH RESOLUTION ASCAT PASS SHOWED N TO NE WINDS OF 20 TO 30 KT 
ACROSS THE GULF OF TEHUANTEPEC. EXPECT WINDS TO PEAK AGAIN THU 
MORNING DUE TO LOCAL DIURNAL EFFECTS BUT WILL REMAIN AT 20 KT.  
SEAS GENERATED BY THE ENHANCED N-NE WINDS IN THE REGION HAVE 
SPREAD WSW AND MERGED WITH LARGER LONG PERIOD SW SWELL FROM THE 
SOUTHERN HEMISPHERE. EXPECT SEAS TO REMAIN IN THE 8-10 FT RANGE 
S OF THE MONSOON TROUGH BETWEEN 100W AND 120W AS THE ENTIRE 
TROUGH BECOMES MORE ACTIVE AND WINDS STEADILY INCREASE IN THE 
AREA. 

SMALL AREA OF FRESH NE TRADE WINDS IS EXPECTED TO PERSIST W OF 
136W BETWEEN 10N AND 16N...WITH SEAS 8 TO 9 FT.

$$
GR