000
AXPZ20 KNHC 292205
TWDEP 

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

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 
2145 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 INTENISTY. 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.

...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 FRM 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 FIRE UP THE CONVECTION ASSOCIATED 
WITH THE LOW PRES UNDER SPECAIL FEATURE AS WELL AS THE OTHER LOWS
DESCRIBED UNDER ICZ/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 
32N1330 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 SWELSL STILL LINGER OVER THE AREA FROM 10N-19N
W OF 126W.

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...
A COLD FRONT OVER THE FAR SE PART OF THE SW GULF OF MEXICO IS 
FOLLOWED BY A COOLER AND DRIER AIRMASS. THIS DENSER AIR HAS
MIXED DOWNWARD BRINGING N-NE WINDS OF 20-30 KT THROUGH THE GULF 
OF TEHUANTEPEC WITH SEAS OF 8-11 FT. THE ASCAT PASS FROM NEAR
1630 UTC THIS AFTERNOON CONFIRMED THESE WINDS. WITH THE TIGHT
PRES GRADIENT IN PLACE OVER SE MEXICO...THESE WIND CONDITIONS 
ARE FORECAST TO GRADUALLY DIMINISH TO 20-25 KT BY TUE MORNING
...AND TO 20 KT OR LESS BY EARLY TUE EVENING WITH SEAS OF 8 FT.

$$
AGUIRRE