000
AXPZ20 KNHC 131557
TWDEP 

TROPICAL WEATHER DISCUSSION NWS 
TPC/NATIONAL HURRICANE CENTER 
1605 UTC WED SEP 13 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 
1545 UTC.

...SPECIAL FEATURES..
A 1009 MB LOW PRES IS LOCATED ALONG THE SOUTH-CENTRAL COAST OF 
MEXICO NEAR 14N100W AND EXTENDS SOUTHWARD INTO THE PACIFIC OCEAN 
FOR A FEW HUNDRED MILES.  THE ASSOCIATED THUNDERSTORM ACTIVITY 
HAS BECOME A LITTLE MORE CONCENTRATED THIS MORNING...AND THIS 
SYSTEM HAS THE POTENTIAL TO BECOME A TROPICAL DEPRESSION DURING 
THE NEXT DAY OR SO AS IT MOVES WEST-NORTHWESTWARD AT ABOUT 10 
MPH.  EVEN IF A DEPRESSION DOES NOT FORM...THIS SYSTEM COULD 
PRODUCE SOME HEAVY RAINFALL DURING THE NEXT COUPLE OF DAYS ALONG 
PORTIONS OF THE PACIFIC COAST OF MEXICO FROM ACAPULCO WESTWARD 
TO MANZANILLO. SCATTERED MODERATE/STRONG CONVECTION N OF 12N 
FROM 98W-104W. SIMILAR CONVECTION IS ALSO FOUND ALONG THE 
MEXICAN COAST FROM 17N-23N.

...ITCZ...
ITCZ AXIS CENTERED ALONG 8N78W 13N96W 12110W 10N120W 10N140W. 
SCATTERED MODERATE/ISOLATED STRONG CONVECTION WITHIN 90 NM OF 
COAST OF COLOMBIA AND OVER THE GULF OF PANAMA. CLUSTERS OF 
SCATTERED MODERATE CONVECTION WITHIN 250 NM N OF AXIS BETWEEN 
110W-129W. 

...DISCUSSION...
MID/UPPER LEVEL TROUGH AT THE EDGE OF NW CORNER OF FORECAST AREA 
FINDING STRONG RESISTANCE IN HEALTHY BROAD WELL ANCHORED 
ANTICYCLONE OVER CENTRAL MEXICO NEAR 25N100W. A RIDGE EXTENDS 
FROM THIS ANTICYCLONE ACROSS BAJA PENINSULA TO BEYOND 16N140W.
DRY AIR RESULTING IN STRONG SUBSIDENCE N OF 20N W OF 110W. SRN 
PERIPHERY OF RIDGE HAS PLENTY OF CONVECTIVE ACTIVITY DUE TO 
ABUNDANT MOISTURE AND GOOD DIFFLUENT PATTERN ALOFT. THE RIDGE IS 
ALSO BUILDING ACROSS THE SOUTHWESTERN U.S..CYCLONIC VORTEX OVER 
ARIZONA HAS WEAK TROUGH ALONG 110/111W.

A 1009 MB LOW PRES AT 12N117W MOVING W 10 KT WITH WELL DEFINED 
UPPER LEVEL DIFFLUENT FLOW. AREAS OF SCATTERED MODERATE/STRONG 
CONVECTION FROM 10N-15N BETWEEN 111W-120W. 

THE CROSS EQUATORIAL LOW LEVEL FLOW S OF 10N WEST OF 95W IS IN 
THE 15-20 KT RANGE. THE SUBTROPICAL RIDGE WELL NW OF AREA IS 
PRODUCING NE TO E WINDS OF 15-20KT FROM 15N-22 WEST OF 120W. 
TYPICAL STRATOCUMULUS CLOUDS COVER THE NW QUADRANT OF THE 
FORECAST AREA.

$$
GR