000
AXPZ20 KNHC 202133
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC FRI OCT 20 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2115 UTC.

...SPECIAL FEATURE...

A 1005 MB LOW IS CENTERED NEAR 16N103W OR ABOUT 140 NM SW OF 
ZIHUATANEJO MEXICO MOVING W 8 KT. VISIBLE SATELLITE IMAGERY 
INDICATES THAT THE LOW HAS A WELL-DEFINED CIRCULATION IN THE 
MID-LEVELS WITH SOME CURVED BANDING BECOMING MORE APPARENT. 
HOWEVER...THE LOW-LEVEL CIRCULATION REMAINS RATHER DISORGANIZED 
AND NON-CIRCULAR...AND THE CENTER IS DISPLACED JUST E OF THE 
DEEP CONVECTION. THE LOW IS CURRENTLY EXPERIENCING STRONG 
EASTERLY SHEAR ON THE S SIDE OF A MID/UPPER LEVEL ANTICYCLONE 
CENTERED OVER THE GULF OF MEXICO...BUT IT IS EXPECTED TO MOVE 
AWAY FROM THE INFLUENCE OF THE HIGH OVER THE NEXT FEW DAYS. 
TROPICAL CYCLONE DEVELOPMENT IS POSSIBLE WITHIN THE NEXT 24-36 
HOURS WITH THIS SYSTEM. SCATTERED MODERATE/STRONG CONVECTION 
FROM 14N-17N BETWEEN 101W-106W.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 12N85W 14N98W 9N110W 11N127W 8N140W. 
SCATTERED MODERATE CONVECTION FROM 8N-13N BETWEEN 85W-94W. 
SCATTERED MODERATE WITHIN 90 NM OF THE AXIS W OF 130W.

...DISCUSSION...

A CUT-OFF MID/UPPER LEVEL LOW IS LOCATED OVER THE N PART OF THE 
DISCUSSION AREA NEAR 24N128W AND IS EXPECTED TO ONLY SLOWLY LIFT 
NE OVER THE NEXT 24 HRS. A BROAD SWATH OF DRY AIR EXTENDS UP TO 
600-700 NM S/SW OF THE LOW AND THEN TURNS NEWD TOWARDS THE BAJA 
PENINSULA. THE LOW-LEVELS ARE QUITE DRY W OF THE BAJA PENINSULA 
AS WELL...AND SKIES ARE GENERALLY CLEAR N OF 23N E OF 123W. A 
WEAK UPPER RIDGE AXIS EXTENDS FROM 10N120W TO 8N140W OVER THE 
ITCZ...AND ASSOCIATED UPPER DIFFLUENCE IS ENHANCING CONVECTION 
NEAR THE AXIS W OF 125W.

FARTHER E...THE UPPER FLOW IS MAINLY EASTERLY AND IS DOMINATED 
BY A FAIRLY STRONG UPPER HIGH CENTERED OVER THE SW GULF OF 
MEXICO. AN INVERTED UPPER TROUGH IS LOCATED ALONG 96W AND IS 
MOVING SLOWLY W EMBEDDED IN THE FLOW. AN AXIS OF MOISTURE 
EXTENDS N/NE OF THE TROUGH AND IS ALLOWING SCATTERED TSTMS TO 
DEVELOP OFF THE MEXICAN/CENTRAL AMERICAN COAST BETWEEN COSTA 
RICA AND THE LOW NEAR 16N103W.

$$
BERG