000
AXPZ20 KNHC 090237
TWDEP 

TROPICAL WEATHER DISCUSSION                                      
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
0405 UTC THU OCT 09 2014

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 
0230 UTC.                       

...TROPICAL LOWS AND WAVES...                                    
 
LOW PRESSURE CONTINUES ALONG THE MONSOON TROUGH AT 10N87W AND IS 
ESTIMATED AT 1007 MB BASED ON TWO RECENT SHIP OBSERVATIONS. 
SCATTERED MODERATE ISOLATED STRONG CONVECTION IS CURRENTLY ONLY 
OBSERVED WITHIN 240 NM OVER THE SE SEMICIRCLE...BUT CONVECTION 
HAD FLARED CLOSER EARLIER. CYCLONIC 10-15 KT WINDS CONTINUE 
WITHIN ABOUT 120 NM OF THE CENTER. THIS LOW PRESSURE IS FORECAST 
TO MOVE NW REACHING NEAR 11N88W ON THU WITH LITTLE CHANGE IN 
WINDS AND SEAS. THE LOW IS FORECAST TO REACH NEAR 11N90W LATE 
FRI WITH WINDS INCREASING TO TO 15-20 KT WITHIN 180 NM OF THE 
CENTER. SEAS WILL THEN INCREASE TO 6-8 FT WITHIN 240 NM SE OF 
THE CENTER IN MIXING WIND WAVE AND CROSS EQUATORIAL SOUTHERLY 
SWELL. BY THEN CONDITIONS WILL BECOME MORE FAVORABLE FOR 
STRENGTHENING...WITH TROPICAL CYCLONE FORMATION POSSIBLE...AS 
THE LOW DRIFTS W TO NEAR 12N90W ON SAT...NEAR 12N91W ON SUN AND 
NEAR 12N93W ON MON.  
   
A TROPICAL WAVE IS ANALYZED FROM 07N95W TO ACROSS EXTREME  
SOUTHEASTERN MEXICO. ISOLATED MODERATE TO STRONG CONVECTION 
CONTINUES TO FLARE WITHIN 45 NM OF THE WAVE AXIS.

A 1012 MB LOW PRESSURE HAS SEPARATED FROM THE ITCZ NEAR  
12.5N139W WITH A TROUGH EXTENDING NE TO NEAR 15N135W. THE NE 
TRADES ARE ENHANCED TO 15-20 KT ACROSS THE SMALL PORTION OF THE  
DISCUSSION WATERS W OF THE LOW AND TROUGH...WITH SEAS OF 6-7 FT 
IN MIXED NW AND SE SWELL. AN UPPER ANTICYCLONE IS CENTERED JUST 
W OF THE AREA AT 14N142W WITH UPPER DIFFLUENCE ENHANCING 
SCATTERED MODERATE ISOLATED STRONG CONVECTION WITHIN 90 NM OF 
THE LOW AND TROUGH. EXPECT THE CONVECTION TO PERSIST TONIGHT 
WITH THE LOW LEVEL SYSTEM AND ASSOCIATED CONDITIONS SHIFTING W 
OF THE AREA EARLY THU.  

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

THE MONSOON TROUGH EXTENDS SW ALONG 10N ACROSS THE SW CARIBBEAN  
FROM THE NW COAST OF COLOMBIA TO ALONG THE CARIBBEAN COAST OF 
PANAMA...THEN TURNS NW ACROSS COSTA RICA INTO AN EMBEDDED 1007 
MB LOW PRESSURE CENTER AT 10N87W. THE MONSOON TROUGH CONTINUES W-
SW THROUGH THE BASE OF A TROPICAL WAVE NEAR 08N95W...THEN TURNS 
SW TO 08N100W...THEN NW TO 11N113W...THEN CONTINUES W ALONG 11N 
TO 122W WHERE SCATTEROMETER WINDS INDICATE A TRANSITION TO AN 
ITCZ WHICH CONTINUES SW TO BEYOND 08N140W.

SCATTERED MODERATE ISOLATED STRONG CONVECTION IS OBSERVED OVER 
AND TO THE S OF THE MONSOON TROUGH WITHIN 120 NM EITHER SIDE OF
A LINE FROM 07N94W TO 08N103W TO 09N112W TO 07N125W...AND ALSO
WITHIN 60 NM EITHER SIDE OF A LINE FROM 13N117W TO 08N131W. 

A LOW LEVEL TROUGH IS ANALYZED N OF THE MONSOON TROUGH AND ITCZ 
FROM 12N125W TO 17N119W. SCATTERED MODERATE ISOLATED STRONG 
CONVECTION IS OBSERVED WITHIN 90 NM OF THE TROUGH AXIS. UPPER 
CONDITIONS WILL GRADUALLY BECOME LESS FAVORABLE FOR SIGNIFICANT 
CONVECTION AS THIS TROUGH CONTINUES WESTWARD OVER THE NEXT DAY 
OR SO.

SCATTERED MODERATE ISOLATED STRONG CONVECTION IS OBSERVED OVER 
AND WITHIN 90 NM OF THE COAST OF CENTRAL AMERICA FROM 87W TO 
92W. SIMILAR CONVECTION HAS ALSO MOVED SW OFF THE PACIFIC COAST 
OF CENTRAL MEXICO AND IS CURRENTLY OBSERVED WITHIN 120 NM EITHER 
SIDE OF LINE FROM 16N103W TO 20N107W.

...DISCUSSION...                                                

THE REMNANTS OF FORMER TROPICAL CYCLONE SIMON HAVE WEAKEN TO A  
TROUGH FROM 23N113W TO 32N112W. AN UPPER LEVEL CYCLONE HAS MOVED 
E OVER SOUTHERN CALIFORNIA WITH THE ASSOCIATED SOUTHWESTERLY 
UPPER FLOW TO ITS S STILL ADVECTING CONVECTIVE DEBRIS MOISTURE 
NE ACROSS THE SW CONUS...WITH SOME OF THE MOISTURE CONTINUING
E ACROSS THE CENTRAL CONUS. 

GULF OF TEHUANTEPEC...THE NORTHERLY NOCTURNAL DRAINAGE FLOW 
ACROSS THE GULF OF TEHUANTEPEC IS EXPECTED TO INCREASE TO 20-25  
KT LATER TONIGHT THROUGH LATE MORNING ON THU...WITH SEAS 
BUILDING TO 8 FT. THE NORTHERLY NOCTURNAL DRAINAGE FLOW IS 
LIKELY TO INCREASE TO 20 KT LATE EACH NIGHT THROUGH SUNRISE  
EACH MORNING THROUGH THE UPCOMING WEEKEND...ESPECIALLY AS THE 
LOW PRESSURE TO THE SE OF TEHUANTEPEC STRENGTHENS. 

LONG PERIOD NW SWELL IS EXPECTED TO REACH THE FAR NW PORTION
OF THE DISCUSSION AREA LATE FRI IN THE FORM OF COMBINED SEAS 
OF 8-11 FT. THESE SEAS WILL PROPAGATE SE ACROSS THE AREA 
REACHING THE PACIFIC COAST OF THE NORTHERN BAJA PENINSULA LATE 
SUN NIGHT...AND SPREAD SE INTO THE TROPICAL WATERS AS FAR SE 
AS 20N115W BY LATE MON. THE SEAS ARE EXPECTED TO BEGIN TO 
SUBSIDE ON MON NIGHT WITH SEAS ACROSS THE ENTIRE WATERS W OF 
112W BELOW 8 FT BY LATE TUE. 

$$
NELSON