000
AXPZ20 KNHC 292214 CCA
TWDEP 

TROPICAL WEATHER DISCUSSION...CORRECTED 
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC MON OCT 29 2012

CORRECTED TO INCLUDE MENTION OF ASCAT WINDS ASSOCIATED WITH 
SPECIAL FEATURE LOW UNDER DISCUSSION SECTION

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 
2200 UTC.

...SPECIAL FEATURE...

A 1006 MB LOW PRES LOCATED NEAR 14N115W IS EMBEDDED WITHIN THE 
MONSOON TROUGH. THE LOW REMAINS DISORGANIZED AS EVIDENT IN 
VISIBLE SATELLITE IMAGERY WHERE LOW LEVEL CLOUDS ARE SEEN RACING 
WESTWARD AWAY FROM IT. ASSOCIATED CONVECTION REMAINS DISORGANIZED
...AND CONTINUES IN A DOWNWARD TREND INN TERMS OF INTENSITY. ONLY
SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS 75 NM OF THE 
THE CENTER IN THE NW QUADRANT...AND WITHIN 120 NM OF THE CENTER 
IN THE SE QUADRANT. ALTHOUGH THE LOW CONTINUES TO BE JUST S OF 
OF AN UPPER LEVEL RIDGE...THE UPPER LEVEL SW-W WINDS ACROSS THE
RIDGE HAVE INCREASED ENOUGH TO DISRUPT IT FROM ORGANIZING ANY 
FURTHER. THIS SYSTEM WILL CONTINUE TO HAVE A MEDIUM CHANCE
OF INTENSIFYING INTO A TROPICAL CYCLONE WITHIN THE NEXT 48 HRS
AS IT REACHES TO NEAR 16N117W 1006 MB BY 24 HRS AND TO NEAR 
16N120W 1007 MB IN 48 HRS.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...

MONSOON TROUGH EXTENDS FROM NW COLOMBIA SW TO LOW PRES AT 06N78W 
1009 MB...AND CONTINUES TO NW TO 09N85W TO 09N95W TO LOW PRES AT 
14N105W 1008 MB TO LOW PRES AT 15N115W 1006 MB TO LOW PRES AT 
11N123W 1008 MB TO 09N140W. SCATTERED MODERATE ISOLATED FROM 10N 
TO 14N BETWEEN 122W AND 130W AND WITHIN 60 NM S OF TROUGH 
BETWEEN 131W AND 133W. SCATTERED MODERATE WITHIN 120 NM S OF 
TROUGH BETWEEN 78W AND 81W AND FROM 11N TO 13N BETWEEN 104W AND 
105W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION EXITS FROM
10N-14N BETWEEN 122W-130W...AND ALSO WITHIN 60 NM S OF TROUGH
BETWEEN 131W-133W. SCATTERED MODERATE CONVECTION IS WITHIN 
120 NM S OF TROUGH BETWEEN 78W-81W...AND FROM 11N-13N BETWEEN
104W-105W.

...DISCUSSION...

ALOFT...AN UPPER TROUGH EXTENDS FROM NORTHERN MEXICO WSW TO 
CENTRAL BAJA CALIFORNIA. W OF IT...BROAD MID/UPPER LEVEL 
ANTICYCLONIC FLOW IS PRESENT EXCEPT JUST NW OF THE REGION WHERE
A VERY SHARP SHORTWAVE TROUGH IS PRESSING EASTWARD TOWARDS
THE AREA. ELSEWHERE BROAD MID/UPPER LEVEL CONTINUES OVER THE 
MAJORITY OF THE DISCUSSION AREA ASSOCIATED WITH A MID/UPPER 
LEVEL ANTICYCLONE AT 11N1119W. A DIFFLUENT PATTERN TO THE SW OF 
THE ANTICYCLONE IS HELPING TO FLARE UP THE CONVECTION ASSOCIATED 
WITH THE LOW PRES UNDER SPECIAL FEATURE AS WELL AS WITH THE 
OTHER LOWS DESCRIBED UNDER ITCZ/MONSOON TROUGH. SATELLITE WATER 
VAPOR IMAGERY SHOWS MODERATE SUBSIDENCE WITH A RESULTANT VERY 
DRY AND STABLE AIR MASS OVER MOST OF THE NORTHERN PORTIONS OF 
THE AREA N OF ABOUT 19N. THE VISIBLE IMAGERY REVEALS BROKEN TO 
OVERCAST PATCHES OF STRATOCUMULUS CLOUDS MOVING WSW WITH 
POSSIBLE ISOLATED SHOWERS TO THE N OF 19N AND W OF 123W.

AT THE SURFACE...A 1024 MB HIGH PRES CENTER IS ANALYZED AT 
32N130 WITH A RIDGE EXTENDING SE TO NEAR 23N119W. HIGH PRES 
COVERS THE AREA N OF 21N W OF 122W. NE TRADE WINDS ARE RATHER 
LIGHT TO THE S AND SW OF THE RIDGE WITH SPEEDS OF 10-15 KT 
ACCORDING TO THE ASCAT PASS FROM 1748 UTC. HOWEVER...SEAS TO 
9 FT IN NW SWELLS STILL LINGER OVER THE AREA FROM 10N-19N W OF 
126W. THE SAME ASCAT PASS REVEALED NE-E WINDS OF 20-30 KT 
WITHIN 180 NM OF THE SPECIAL FEATURE LOW IN THE NE QUADRANT...
AND 20-25 KT WINDS WITHIN 240 NM OF THE LOW IN THE SE QUADRANT. 

DEEP CONVECTION REMAINS VERY ACTIVE FOR THIS TIME YEAR ALONG 
AND NEAR THE MONSOON TROUGH DIRECTLY AND INDIRECTLY ASSOCIATED
WITH THE LOW PRESSURE FEATURES MENTIONED EARLIER...INCLUDING
THE ONE UNDER SPECIAL FEATURE.

GAP WINDS...
THE COOLER AND DRIER AIRMASS THAT SETTLED IN OVER THE GULF OF
TEHUANTEPEC THE PAST FEW DAYS WITH FRESH TO STRONG NLY WINDS
HAS THIN OUT ENOUGH TO ALLOW FOR WINDS TO DIMINISH TO 20 KT
THROUGH THE CHIVELA PASS AND INTO THE GULF OF TEHUANTEPEC. 
THESE WINDS ARE FORECAST TO DIMINISH TO 10-15 KT BY WED.

$$
AGUIRRE