000
AXPZ20 KNHC 140244
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL 
0405 UTC MON OCT 14 2013

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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0300 UTC.

...SPECIAL FEATURES...
TROPICAL STORM OCTAVE AT 20.6N113.7W AT 0300 UTC MOVING N-NW OR
335 DEGREES AT 13 KT WITH CENTRAL PRES 995 MB.  WINDS 55 GUSTS
TO 65 KT.  UPPER LEVEL WIND HAS TURNED MORE FAVORABLE...WARM SST
AND ABUNDANT WARM TROPICAL MOISTURE...OCTAVE MAY INTENSIFY
FURTHER AS IT DRIFT JUST OFF SOUTHERN BAJA CALIFORNIA PENINSULA
W COAST.  BANDS AND CLUSTER OF STRONG CONVECTION HAS IMPACTED 
LAND SECTIONS.  OCTAVE IS EXPECTED TO START WEAKENING SOON AND
SLOWLY TURN N AND NE BEFORE MOVING INLAND OVER SOUTHERN BAJA
CALIFORNIA.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...           
MONSOON TROUGH EXTENDS FROM 09N84W TO 1008 MB LOW PRES AT
11N101W THEN RESUME FROM LOW PRES AT 13N117W TO 10N130W TO
BEYOND 10N140W.  SCATTERED MODERATE CONVECTION WITHIN 180 NM
S OF AXIS FROM 85W TO 93W.

...DISCUSSION...
UPPER LEVEL TROUGH REMAINS IN PLACE FROM SOUTHERN CALIFORNIA 
THROUGH 32N116W TO 12N140W...MAKING LITTLE EASTWARD PROGRESS AS 
BROAD AND DOMINANT UPPER LEVEL ANTICYCLONE REMAINS ANCHORED OVER 
CENTRAL MEXICO.  UPPER LEVEL TROUGH CONTINUES TO MAINTAIN A VERY
DRY...STABLE...SUBSIDING AIR MASS OVER THE BASIN W OF ITS AXIS.

UPPER LEVEL ANTICYCLONE OVER CENTRAL MEXICO HAS FINALLY BEGIN TO 
MOVE EASTWARD ALLOWING UPSTREAM UPPER LEVEL TROUGH TO INCH E AND
BRING ITS DRY AIR MASS CLOSER TO OCTAVE AND LOW PRES CENTER AT 
13N117W.  ALSO MAY PERMIT OCTAVE TO SHIFT MORE N AND NE THAN
PRESENT N-NW TRACK...BRINGING IT INLAND MEXICO.  

...ELSEWHERE AT THE LOWER LEVELS...
TROPICAL MOISTURE CHANNEL PREVIOUSLY FEEDING MONSOON TROUGH HAS
BEEN INTERRUPTED AND NOW LARGE SLOT OF DRY AIR MASS COVER N OF
08N E OF 101W.  WHILE AFOREMENTIONED SYSTEMS ARE ALREADY
EMBEDDED IN MOISTURE...A NEW LOW PRES 1008 MB NOTED AT 11N102W 
HAS ABSOLUTELY LITTLE MOISTURE AVAILABLE FOR CONVECTION AND 
MONSOON TROUGH E OF 101W IS QUICKLY DRYING OUT.

LOW PRES CENTER AT 13N117W...ALTHOUGH POSSIBLE TROPICAL CYCLONE
...IS HINDERED BY UPPER LEVEL OUTFLOW FROM T.S. OCTAVE...WHICH 
ALSO ENCOUNTERED ADVERSE ENVIRONMENT ALOFT AND STILL MANAGED TO
DEVELOP INTO STRONG CYCLONE. 

FARTHER W...WEAK REMNANT LOW PRES OF NARDA MOVED W OF 140W BUT 
STILL HAS A MINOR EFFECT ON SEAS CLOSE TO ITS NE QUADRANT.  

GULF OF TEHUANTEPEC...REMNANTS OF TROPICAL WAVE OVER W CENTRAL
AMERICA ALONG WITH WEAK HIGH PRES OVER CENTRAL MEXICO HELP USHER
IN FRESH TO STRONG NORTHERLY WINDS AND RESULTANT SEAS TO 8 FT IN
GULF OF TEHUANTEPEC TONIGHT.  CONDITIONS PERSIST THROUGH MON...
DIMINISHING MON NIGHT.
 
$$
WALLY BARNES