000
AXPZ20 KNHC 060949
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC SUN NOV 06 2011

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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
09450 UTC.

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

THE MONSOON TROUGH EXTENDS E TO W ALONG 10N FROM 75W TO 85W... 
THEN TURNS SW TO 07N95W...THEN CONTINUES NW TO 12N106W.
LOW LEVEL WINDS INDICATE THE ITCZ BEGINS NEAR 10N110W AND 
CONTINUES SW TO 07N132W TO BEYOND 10N140W. LIGHTNING DATA 
INDICATES A FEW VERY SMALL CLUSTERS OF TSTMS OVER THE PACIFIC 
WATERS N OF 03N TO THE E OF 80W AND ALONG THE PACIFIC COAST OF 
COSTA RICA. ISOLATED STRONG CONVECTION IS NOTED WITHIN 30 NM OF 
13N108W AND 08N114.5W AND 08N126W. 

A LOW LEVEL TROUGH EXTENDS NE TO SW FROM 11N108W TO NEAR 16N106W
AND SEPARATES THE MONSOONAL FLOW FROM THE ITCZ ZONE. THIS TROUGH 
IS ACCOMPANIED BY OVERCAST LOW AND MID LEVEL CLOUDS WITH ONLY A 
FEW EMBEDDED TSTMS. THE TROUGH IS EXPECTED TO AMPLIFY FURTHER NE 
AS THE TROUGH DRIFTS W OVER THE NEXT FEW DAYS.      

...DISCUSSION...

A LONG WAVE TROUGH OVER WESTERN N AMERICA HAS ITS MEAN AXIS 
CONTINUING S OVER THE DISCUSSION AREA FROM 32N120W TO 17N115W 
RESULTING IN ZONAL UPPER FLOW OVER THE AREA TO THE N OF 25N. A 
NARROW BAND OF UPPER MOISTURE IS NOTED ALONG 30N FROM 138W TO 
128W...THEN BROADENS AS IT TURNS NE ACROSS THE NORTHERN BAJA 
CALIFORNIA PENINSULA AND GULF OF CALIFORNIA...EVENTUALLY FANNING 
OUT OVER SE ARIZONA AND MOST OF NEW MEXICO. IMMEDIATELY TO THE S 
OF THIS MOISTURE IS A BAND OF VERY DRY AIR ROUGHLY WITHIN 120 NM 
EITHER SIDE OF A LINE FROM 28N140W TO 28N130W TO 24N114W TO 
BEYOND 32N97W. 

A UPPER CYCLONE IS OVER THE DEEP TROPICS NEAR 04N108W AND 
EFFECTIVELY SEPARATES AN UPPER RIDGE WITH NORTHWESTERLY FLOW 
OVER THE SW PORTION FROM BROAD ANTICYCLONIC FLOW ASSOCIATED WITH 
AN UPPER ANTICYCLONE NEAR 10N88W. UPPER DIFFLUENCE CONTINUES TO 
ENHANCE THE INTERMITTENT CONVECTION ASSOCIATED WITH THE SURFACE 
TROUGH NEAR 13N106W. THE DEBRIS MOISTURE IS ADVECTED NE ALONG 
THE PERIPHERY OF THE EASTERN UPPER RIDGE OVER CENTRAL OLD MEXICO 
NEAR 19N98W. A LARGE TROPICAL MOISTURE PLUME...ORIGINATING IN 
THE CENTRAL PACIFIC...CONTINUES E WITHIN 360 NM EITHER SIDE OF A 
LINE FROM 16N140W TO 16N120W...THEN THE PLUME NARROWS AS IT 
TURNS NE IN RESPONSE TO THE LONG WAVE UPPER TROUGH...AND 
CONTINUES NE ACROSS OLD MEXICO AND THE WESTERN GULF OF MEXICO 
FROM 20N110W TO BEYOND 30N92W. THE UPPER LEVELS ARE VERY DRY S 
OF 06N W OF 105W AND S OF 15N E OF 105W.
      
AT THE LOW LEVELS A COLD FRONT IS WASHING OUT OVER NORTHERN OLD 
MEXICO WHILE A SECOND COLD FRONT HAS REACHED ALONG 32.5N NEAR 
130W...AND IS SLIDING SE TO THE N OF A RIDGE THAT EXTENDS FROM 
32N140W TO 20N110W. NORTHERLY WINDS AT 15 TO 20 KT CONTINUES 
BEHIND THE INITIAL FRONT...TO THE N OF 27N E OF 118W...AND IS 
EXPECTED BRIEFLY BEHIND THE SECOND FRONT. NE TRADES AT 15 TO 20 
KT CONTINUE SW OF THE RIDGE IN THE AREA FROM 10N TO 22N W OF 
121W. MIXED N SWELL RESULTS IN COMBINED SEAS OF 8 TO 13 FT OVER 
THE WATERS N OF 10N W OF 112W AND WILL SOON MIX WITH SE AND SW 
SWELL COMPONENTS.

GULF OF CALIFORNIA...NW WINDS ARE EXPECTED TO INCREASE 15 TO 20 
KT BEHIND THE SECOND COLD FRONT MON NIGHT.

$$
NELSON