000
AXPZ20 KNHC 151554
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC SUN OCT 15 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...
TROPICAL DEPRESSION NORMAN NEAR 19.0N 104.8W AT 15/1500 UTC OR ABOUT 
35 MILES... 55 KM...WEST OF MANZANILLO MEXICO. NORMAN HAS MAXIMUM 
SUSTAINED WINDS OF 30 KT GUSTS 40 KT WITH ESTIMATED CENTRAL PRESSURE 
1000 MB. NORMAN IS MOVING NNE 8 KT. NORMAN HAS A RATHER LARGE 
ENVELOPE AND IS FAIRLY WELL ORGANIZED WITH BANDS OF SCATTERED TO 
NUMEROUS TSTMS WITHIN 150-180 NM OF THE CENTER OF THE SW 
SEMICIRCLE.  NORMAN IS EXPECTED TO CROSS THE COASTLINE LATER THIS 
AFTERNOON AND THERE IS STILL THE POTENTIAL FOR NORMAN TO BECOME A 
TROPICAL STORM BEFORE LANDFALL. NORMAN IS EXPECTED TO PRODUCE 
RAINFALL ACCUMULATIONS OF 6 TO 12 INCHES WITH ISOLATED MAXIMUM 
AMOUNTS OF 15 INCHES OVER PORTIONS OF SOUTHWESTERN MEXICO.  THESE 
RAINS COULD CAUSE LIFE-THREATENING FLASH FLOODS AND MUD SLIDES IN 
AREAS OF MOUNTAINOUS TERRAIN. SEE LATEST NHC FORECAST ADVISORY UNDER 
AWIPS/WMO HEADERS MIATCMEP5/WTPZ25 KNHC FOR MORE DETAILS. 

...TROPICAL WAVES...
TROPICAL WAVE ALONG 100W N OF 7N MOVING W 10-15 KT.  THIS WAVE IS 
EXPECTED TO BECOME ABSORBED INTO THE LARGER DISTURBANCE ASSOCIATED 
WITH TROPICAL DEPRESSION NORMAN WITHIN THE NEXT 24 HOURS. 

TROPICAL WAVE HAS ENTERED THE DISCUSSION AREA N OF 4N ALONG 81W AND 
EXTENDS ACROSS PANAMA INTO THE CARIBBEAN. 

...ITCZ...
AXIS ALONG 8N81W 5N86W 11N94W 14N108W 10N115W 12N140W. SCATTERED 
MODERATE ISOLATED STRONG WITHIN 120 NM OF AXIS BETWEEN 83W AND 112W.

...DISCUSSION...
UPPER LEVELS...
MID TO UPPER LEVEL TROUGH/SHEAR AXIS EXTENDS FROM A CYCLONIC 
CIRCULATION OVER ARIZONA WWD THROUGH 27N120W 26N130W 27N135W. 
MODERATE TO STRONG SUBSIDENCE IS INDICATED WITHIN 90-120 NM EITHER 
SIDE OF THE SHEAR AXIS. BROAD ANTICYCLONIC FLOW COVERS THE AREA N OF 
THE SHEAR AXIS. A BROAD RIDGE COVERS THE REMAINDER OF THE PACIFIC S 
OF THE SHEAR AXIS WITH AN ANTICYCLONE NEAR 10N136W AND ANOTHER JUST 
TO THE E OF TROPICAL DEPRESSION NORMAN OVER THE SOUTHERN BAY OF 
CAMPECHE. MODERATE SWLY FLOW BETWEEN THE SHEAR AXIS AND THE 
ANTICYCLONE OVER THE BAY OF CAMPECHE WAS PROVIDING AN OUTFLOW 
CHANNEL FOR NORMAN. MODERATE EASTERLY FLOW AT THE MID AND UPPER 
LEVELS PREVAILS OVER THE TROPICAL PACIFIC E OF 100W. 

CONVECTION WITHIN THIS AREA IS LARGELY CONFINED TO THE ITCZ REGION.  
ONE EXCEPTION IS AN AREA OF NORTH OF THE ITCZ WEST OF 135W EXTENDING 
NORTH TO 17N...THIS IS DUE TO A DEEP LAYER SMALL LOW JUST WEST OF 
THE AREA.  

SURFACE...
WEAK RIDGE NORTH OF 17N WEST OF 117W.  REMAINDER OF THE AREA OUTSIDE 
THE TROPICAL DEPRESSION IS ANALYZED AS A BROAD TROUGH.

$$
COBB