000
AXPZ20 KNHC 060316
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC TUE NOV 06 2007

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

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0300 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 6N77W 9N86W 6N98W 12N121W 9N131W 
11N140W. SCATTERED MODERATE CONVECTION WITHIN 60 NM OF AXIS 
BETWEEN 80W-91W...BETWEEN 111W-116W...AND BETWEEN 127W-133W.

...DISCUSSION...

E OF 120W...
A STRONG MID/UPPER LEVEL ANTICYCLONE IS ANCHORED OVER S/CENTRAL 
MEXICO WITH A RIDGE AXIS EXTENDING E/W ALONG 19N...AND PRODUCING 
AN EXTENSIVE AREA OF MODERATE/STRONG SUBSIDENCE E OF 116W EXCEPT 
FOR PARTS OF CENTRAL AMERICA AND THE ADJACENT WATERS. DEEP 
EASTERLY FLOW JUST S OF THE RIDGE AXIS IS ADVECTING MOISTURE 
FROM THE W CARIBBEAN ACROSS CENTRAL AMERICA TO NEAR 100W. A 
DECAYING FRONTAL BOUNDARY IS BANKED ALONG THE N SLOPES OF THE 
CENTRAL AMERICAN MOUNTAIN RANGE AND MUCH OF THE CLOUDINESS AND 
ASSOCIATED SHOWERS ARE OCCURRING OVER THE NE PARTS OF 
NICARAGUA...HONDURAS...AND GUATEMALA. HOWEVER...A FEW SHOWERS/ 
TSTMS ARE OCCURRING NEAR THE PACIFIC COASTS OF THESE COUNTRIES 
AS WELL AS OVER PANAMA AND COSTA RICA DUE TO A NWD INFLECTION OF 
THE ITCZ BETWEEN 80W-95W. FARTHER W...THE UPPER RIDGE AXIS 
EXTENDS NW THROUGH THE GULF OF CALIFORNIA DUE TO INCREASED 
SOUTHERLY FLOW W OF THE BAJA PENINSULA AND A WEAK UPPER LEVEL 
LOW/TROUGH LOCATED NEAR 8N116W. UPPER DIFFLUENCE BETWEEN THE LOW 
AND RIDGE ARE ENHANCING CONVECTION ALONG THE ITCZ BETWEEN 
112W-117W.

MINIMAL GALE CONDITIONS CONTINUE OVER THE GULF OF TEHUANTEPEC 
BUT GFS AND NAM GUIDANCE SUGGEST THAT WINDS COULD INCREASE TO 
NEAR 45 KT BY TUE EVENING. THE GALE WILL CONTINUE FOR THE NEXT 
SEVERAL DAYS DUE TO HIGH PRES SETTING UP OVER THE GULF OF 
MEXICO...BUT COULD DECREASE BELOW WARNING CRITERIA WITHIN 72 HRS 
OR SO (BY THU EVENING).

W OF 120W...
A NEARLY STATIONARY UPPER LEVEL TROUGH...ANCHORED BY A CUT-OFF 
LOW JUST W OF SAN FRANCISCO CALIFORNIA...LIES ACROSS THE NW PART 
OF THE AREA WITH AXIS ALONG 131W N OF 17N. A WEAK SUBTROPICAL 
JET CURVES THROUGH THE BASE OF THE TROUGH FROM 24N140W TO 
20N130W NEWD TO 30N119W AND THE CALIFORNIA/MEXICO BORDER. A 
BROKEN STRATOCUMULUS FIELD IS N OF 20N BETWEEN 115W-132W BUT THE 
SUBTROPICAL RIDGE HAS WEAKENED ENOUGH THAT THE CLOUD FIELD IS 
SHRINKING WITHOUT REINFORCEMENT FROM THE N. FARTHER S...AN UPPER 
LEVEL ANTICYCLONE LIES JUST W OF THE AREA WITH A RIDGE AXIS 
ALONG 11N. A SURFACE TROUGH APPEARS EMBEDDED WITHIN THE ITCZ 
NEAR 121W WITH SCATTERED SHOWERS OCCURRING MAINLY TO THE E IN A 
REGION OF UPPER LEVEL DIFFLUENCE.

$$
BERG