000
AXPZ20 KNHC 070956
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC WED NOV 07 2007

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. 

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0945 UTC.

...ITCZ...
ITCZ AXIS IS CENTERED ALONG 9N78W 9N104W 10N118W 8N140W. 
SCATTERED MODERATE ISOLATED STRONG CONVECTION IS NOTED WITHIN 90 
NM OF AXIS BETWEEN 85W AND 102W AND FROM 7N TO 11N BETWEEN 115W 
AND 125W AND WITHIN 90 NM OF AXIS W OF 132W.

...DISCUSSION...
AN UPPER CUT-OFF CYCLONE CONTINUES QUASI-STATIONARY N OF AREA 
NEAR 34N126W WITH A TROUGH S THROUGH 20N125W...BECOMING NARROW 
TO A BASE AT 11N122W. A SECONDARY UPPER TROUGH IS SWINGING SE 
AROUND THE CYCLONE ALONG 32N129W 27N133W. DRY UPPER AIR IS NOTED 
OVER THE DISCUSSION AREA N OF 28N BETWEEN 120W AND 138W. TO THE 
SW OF THESE TROUGHS...AN UPPER RIDGE STILL PUSHES INTO THE SW 
CORNER OF AREA WITH AN ILL-DEFINED CREST ALONG 22N140W 14N130W 
7N140W. UPPER MOISTURE...ORIGINATING WELL W OF AREA...IS 
INDICATED WITHIN 180 NM EITHER SIDE OF LINE 25N126W 17N140W. 
DEBRIS MOISTURE...FROM ENHANCED ITCZ CONVECTION BETWEEN 115W AND 
123W...CONTINUES TO STREAM N ALONG THE W PERIPHERY OF A LARGE 
UPPER RIDGE DESCRIBED BELOW. THIS MOISTURE PLUME IS NARROW ALONG 
18N121W 26N119W TO 32N117W WHERE THE PLUME FANS OUT OVER 
SOUTHERN CALIFORNIA...BUT A BRANCH CONTINUES TO TURN E OVER THE 
CONUS ALONG 33N...WITH SOME THIS MOISTURE NOW STREAMING ACROSS 
SOUTHERN LOUISIANA AND OVER THE UPPER LEVELS OF THE N CENTRAL 
GULF OF MEXICO.       
   
AN UPPER ANTICYCLONE IS ESTIMATED NEAR JAMAICA WITH AN UPPER 
RIDGE EXTENDING W ACROSS OLD MEXICO ALONG 20N TO A CREST OVER 
THE PAC ALONG 10N108W 17N121W 28N122W 32N107W. A PERSISTENT 
FRONTAL TROUGH OVER THE W CARIBBEAN LIES UNDER THIS UPPER RIDGE 
WITH SCATTERED CONVECTION ENHANCED FROM 10N TO 18N BETWEEN 80W 
AND 87W. CONVECTION ALONG THE E PAC ITCZ IS ALSO ENHANCED ALONG 
9N BETWEEN 79W AND 101W. THE RESULTANT DEBRIS MOISTURE IS 
TRAPPED ROUGHLY FROM 8N TO 17N BETWEEN 80W AND 104W. THE UPPER 
LEVELS OF THE TROPICAL PAC APPEAR VERY DRY S OF 7N.     

A LOW LEVEL RIDGE EXTENDS FROM 32N138W TO 12N110W AND IS 
EXPECTED TO CHANGE LITTLE THROUGH 48 HOURS. THE GRADIENT S OF 
RIDGE WILL CONTINUE TO SUPPORT NE TO E WINDS IN 20 KT RANGE 
THROUGH 48 HOURS. N WINDS ALONG W COAST BAJA PENINSULA IN THE 15 
KT RANGE...EXCEPT TO NEAR 20 KT NEAR SOUTHERN TIP OF THE BAJA 
PENINSULA AT THE MOMENT...BUT THE GRADIENT EXPECTED TO WEAKEN 
AND SUPPORT MOSTLY 15 KT WITHIN 24 HOURS.  

GAP WINDS...GALE WINDS IN AND JUST S OF THE GULF OF TEHUANTEPEC 
ARE NOW EXPECTED TO PERSIST THROUGH 36 HOURS. NLY WINDS 20 KT IN 
THE GULF OF FONSECA AND GULF OF PAPAGAYO THROUGH 48 HOURS.

$$
NELSON