000
AXPZ20 KNHC 110921
TWDEP 

TROPICAL WEATHER DISCUSSION     
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC MON DEC 11 2006

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 
0900 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG...5N77W 6N105W 5N140W.
SCATTERED MODERATE CONVECTION IS WITHIN 30 NM EITHER SIDE OF THE 
ITCZ AXIS WEST OF 130W.

...DISCUSSION...

UPPER LEVELS...
MIDDLE AND UPPER LEVEL SHORTWAVE TROUGH IS OVER THE NORTHWEST 
ONE THIRD OF MEXICO AND IS MOVING EAST.  WITHIN 550 NM NW OF A 
LINE 32N99W TO THE SOUTH TIP OF BAJA CALIFORNIA TO 16N140W AN 
AREA OF DRY AND CLOUD FREE AIR IS OBSERVED IMPLYING UPPER LEVEL 
SUBSIDENCE.  IN THE LOWER LEVEL OVERCAST STRATOCUMULUS IS 
OBSERVED.  REMAINDER OF THE MIDDLE AND UPPER LEVELS IS A RATHER 
FLAT PATTERN.

DRY AIR IN THE MIDDLE AND UPPER LEVELS IS OBSERVED OVER MOST OF 
THE AREA SE OF A LINE 20N106W TO 10N130W TO 5N130W.  MOISTURE 
FROM ITCZ CONVECTION IS WITHIN THIS AREA FROM 2N TO 10N FROM 
103W TO 115W AND ALSO A SMALL AREA NEAR THE COAST OF COSTA RICA.

SURFACE...
STRONG RIDGE IS NORTH OF THE ITCZ WEST OF 110W.  ELSEWHERE BROAD 
TROUGH IS ANALYZED.

GAP WINDS...
GALE FORCE WINDS HAVE DIMINISHED TO 20 TO 30 KT ACROSS THE GULF 
OF TEHUANTEPEC.

$$
LL