000
AXPZ20 KNHC 291546
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC SAT SEP 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC.

...SPECIAL FEATURE...

TROPICAL DEPRESSION NORMAN CENTERED NEAR 26.2N 110.5W AT 1500 
UTC MOVING WNW AT 7 KT. MAXIMUM SUSTAINED WINDS 25 KT GUSTS TO 
35 KT WITH MINIMUM PRESSURE 1006 MB. THE DEPRESSION IS RAPIDLY 
WEAKENING DUE TO LAND EFFECTS...LACKS SIGNIFICANT CONVECTION AND 
WILL BECOME A DIFFUSE REMNANT LOW WITHIN THE NEXT 6 TO 12 HOURS. 
SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS 
MIATCMEP4/WTPZ24 KNHC FOR MORE DETAILS.

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

DISCONTINUOUS MONSOON TROUGH EXTENDS FROM 08N78W TO 09N100W TO 
12N108W...RESUMES FROM TO 16N118W TO 10N134W...THEN CONTINUES AS 
ITCZ TO 09N140W. SCATTERED MODERATE ISOLATED STRONG CONVECTION 
IS WITHIN 75 NM S OF THE MONSOON TROUGH E OF 108W.

...DISCUSSION...

MARINE CONDITIONS ARE BECOMING FAIRLY BENIGN OVER MOST OF THE 
DISCUSSION AREA. DYING REMNANTS OF MIRIAM ARE NEARLY STATIONARY 
NEAR 21N115W WITH SCATTEROMETER SHOWING WINDS 15-20 KT NEAR THE 
CENTER. SEAS ARE SUBSIDING IN THE VICINITY OF THE LOW AS SW WINDS
ASSOCIATED WITH THE MONSOON TROUGH CONTINUE TO DECREASE BETWEEN 
105W AND 125W. MAXIMUM SEAS ARE ESTIMATED AT 8-9 FT NEAR 15N118W 
AND IN THE SE QUADRANT OF EX-MIRIAM NEAR 20N114W.

A WEAK TROUGH EXTENDS INTO NORTH-CENTRAL PORTION OF THE AREA FROM
33N127W TO 28N132W. THE TROUGH HAS RELAXED THE PRES GRADIENT NW 
OF THE CONVERGENCE ZONE BOUNDARY AND SE OF 1023 MB HIGH PRES NEAR
32N142W. SCATTEROMETER PASSES SHOW LIGHT TO MODERATE NE WINDS IN 
THIS AREA...ALTHOUGH NW SWELL FROM A DISSIPATED COLD FRONT WITH 
SEAS TO 9 FT ARE PRESENT NW OF A LONE FROM 30N130W TO 23N140W.
SW CROSS-EQUATORIAL SWELL WITH SEAS TO 7 FT IS ALSO PRESENT S OF 
10N BETWEEN 100W AND 130W. SEA HEIGHTS ARE EXPECTED TO GRADUALLY 
SUBSIDE OVER MOST OF THE AREA OVER THE NEXT 24 TO 48 HOURS EXCEPT
FOR A SMALL AREA OF ENHANCED SW WINDS AROUND 20 KT EXPECTED TO 
DEVELOP S OF THE MONSOON TROUGH WHICH WILL INCREASE SEAS TO 8 FT 
FROM 06N TO 10N BETWEEN 95W AND 103W BY MON.

LOOKING FARTHER AHEAD INTO THE MIDDLE OF NEXT WEEK...A COLD FRONT
SWEEPING ACROSS THE GULF OF MEXICO WILL ALLOW HIGH PRES TO BUILD 
SOUTHWARD INTO SOUTHERN MEXICO MON NIGHT AND TUE WITH FAVORABLE 
CONDITIONS DEVELOPING FOR A MINOR GULF OF TEHUANTEPEC WIND EVENT 
TO COMMENCE TUE NIGHT AND CONTINUE THROUGH THU NIGHT...WITH WINDS
PULSING TO 20-30 KT IN THE EARLY MORNING EACH DAY.

$$
MUNDELL