000
AXPZ20 KNHC 291552
TWDEP 

TROPICAL WEATHER DISCUSSION     
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC FRI DEC 29 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC.

...ITCZ...
AXIS 4N77W 8N97W 6N110W 6N140W. SCATTERED MODERATE ISOLATED 
STRONG WITHIN 180 NM N OF AXIS FROM 95W TO 102W...WITHIN 180 NM 
S OF AXIS FROM 118W TO 123W...AND WITHIN 90 NM EITHER SIDE OF 
AXIS FROM 129W TO 140W.

...DISCUSSION...
UPPER LEVELS...
A MID TO UPPER TROUGH EXTENDS SOUTHWARD ALONG 108W FROM THE 
CUT-OFF LOW CENTERED NEAR THE MEXICO-NEW MEXICO BORDER.  AN 
UPPER RIDGE AXIS EXTENDS NORTHWARD ALONG 130W IN THE AREA.  A 
SECOND UPPER HIGH EXTENDS EASTWARD ALONG 10N FROM THE EXTREME 
EASTERN PACIFIC TO THE CARIBBEAN.  THE GRADIENT BETWEEN THE 
TROUGH AND THE TWO RIDGES IS PRODUCING A JET WITH UP TO 110 KT 
AT 300 MB...WHICH IS ALSO ADVECTING UPPER MOISTURE AND DEBRIS 
CLOUDINESS ACROSS SOUTHERN MEXICO AND CENTRAL AMERICA.  
GENERALLY...NORTH OF 15N AS WELL AS SOUTH OF 8N AND EAST OF 110W 
DRY AND STABLE AIR PREVAILS.

SURFACE...
A 1025 MB HIGH REMAINS IN PLACE NEAR 32N129W.  A TROUGH AXIS 
EXTENDING WEST-SOUTHWESTWARD FROM NEAR SOUTHERN BAJA CALIFORNIA 
TO 16N130W IS THE REMAINS OF A VIGOROUS COLD FRONT.  THERE ARE N 
TO NE WINDS UP TO 20 KT NORTH OF THE TROUGH AXIS.  THESE WINDS 
SHOULD WEAKEN WITHIN THE NEXT 24 HR.  SOUTH OF THE HIGH MODERATE 
NE TRADEWINDS CONTINUE AND MAY INCREASE IN ABOUT TWO DAYS.  A 
DISTURBANCE ALONG THE ITCZ NEAR 102W IS GENERATING SUBSTANTIAL 
CONVECTION...THOUGH POTENTIAL FOR DEVELOPMENT INTO AN OFF-SEASON 
TROPICAL CYCLONE APPEARS TO BE MINIMAL DUE TO STRONG VERTICAL 
SHEAR.

GAP FLOWS...
A GAP FLOW WIND EVENT CONTINUES IN THE GULF OF PAPAGAYO WITH E 
TO NE WINDS UP TO 30 KT AS REVEALED BY THE LATEST QUIKSCAT 
PASS.  AS THE PRESSURE GRADIENT AND CARIBBEAN TRADEWINDS RELAX 
SOME IN THE NEXT DAY OR TWO...THIS GAP FLOW SHOULD ALSO 
WEAKEN...BUT 20 KT WINDS MAY STILL REMAIN THROUGH 48 HR.

$$
LANDSEA