000
AXPZ20 KNHC 042129
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC WED OCT 04 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 
2130 UTC.

...TROPICAL WAVES...

TROPICAL WAVE IS ALONG 94W/95W N OF 2N TO GULF OF TEHUANTEPEC IS 
MOVING W AT 15 KT. SCATTERED MODERATE CONVECTION IS INDICATED 
WELL E OF THE WAVE AXIS GENERALLY FROM 7N TO 9N BETWEEN 90W AND 
93W. OTHERWISE NO SIGNIFICANT CONVECTION DIRECTLY ASSOCIATED 
WITH THE WAVE ITSELF.

TROPICAL WAVE IS ALONG 113W/114W FROM 3N-15N MOVING W 15 KT.  
SCATTERED MODERATE CONVECTION IS INDICATED WITHIN 120 NM EITHER 
SIDE OF THE WAVE AXIS FROM 10N TO 13N. CONVECTION IS NOT
ORGANIZED AT THIS TIME. 

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 9N84W 10N105W 11N115W 10N140W. 
SCATTERED MODERATE ISOLATED STRONG WITHIN 120 NM EITHER SIDE OF 
AXIS BETWEEN 110W AND 135W. SCATTERED MODERATE WITHIN 90 NM 
EITHER SIDE OF AXIS BETWEEN 84W AND 92W...AND WITHIN 120 NM S OF 
THE AXIS BETWEEN 98W AND 105W. 

...DISCUSSION...

HIGHLY AMPLIFIED PATTERN PREVAILS OVER THE DISCUSSION AREA
WITH A BROAD TROUGH COVERING THE AREA GENERALLY N OF 20N AND W 
OF 120W. TROUGH AXIS EXTENDS FROM A WELL DEFINED CYCLONIC 
CIRCULATION OFF THE CA COAST NEAR 38N127W SWWD THROUGH 30N128W 
TO 23N140W. FURTHER E...HIGHLY AMPLIFIED RIDGE EXTENDS FROM THE 
INTER-MOUNTAIN CONUS SWD THROUGH 30N107W TO 15N111W. A LARGE 
AREA OF CONFLUENT SSWLY FLOW EXITS BETWEEN THE TROUGH AND RIDGE 
MANIFESTING ITSELF IN A 350 NM WIDE BAND OF 60-90 KT WINDS AS 
SUGGESTED BY SATELLITE DERIVED WINDS. THESE WINDS WERE ADVECTING 
MID TO UPPER LEVEL TROPICAL MOISTURE NWD INTO THE SW CONUS.  
MODERATE SUBSIDENCE WAS NOTED WITHIN THE RIDGE AXIS ITSELF 
GENERALLY FROM 15N TO 30N BETWEEN 100W AND 115W. FURTHER E 
A SHARP BUT NARROW TROUGH EXTENDS FROM E TEXAS SWD ALONG THE E
COAST OF MEXICO TO A SMALL UPPER LEVEL LOW AT THE BASE OF THE 
TROUGH NEAR TAMPICO/23N99W. DIFFLUENT WNWLY FLOW AT THE MID AND 
UPPER LEVELS PREVAILS ELSEWHERE OVER THE TROPICAL PACIFIC E OF 
105W. THIS FLOW WAS ENHANCING DEEP CONVECTION ALONG THE ITCZ
GENERALLY BETWEEN 90W AND 105W. 

AT THE SURFACE...MODERATE TRADES ARE N OF THE ITCZ TO 20N 
GENERALLY W OF 120W WITH TWO EMBEDDED TROPICAL WAVES...MENTIONED 
ABOVE. FURTHER N...A BROAD E PAC RIDGE IS W OF BAJA CALIFORNIA 
AND COVERS THE AREA N OF 15N AND W OF 110W WITH AXIS ALONG 
30N130W 18N112W. 

GAP WINDS...1246 UTC QUIKSCAT PASS INDICATED N TO NE WINDS OF 
20-25 KT IN THE GULF OF TEHUANTEPEC. ALTHOUGH THE SAME PASS 
MISSED THE GULF OF PAPAGAYO...THERE WERE A COUPLE OF SHIP 
REPORTS OF 20 TO 25 KT WINDS NEAR THE AREA. NWP MODELS INDICATE
WINDS IN THE GULF OF PAPAGAYO SHOULD DECREASE TO LESS THAN 20 KT 
WITHIN 24 HOURS WHILE THE WINDS ARE EXPECTED TO PERSIST IN THE 
GULF OF TEHUANTEPEC FOR AN ADDITIONAL 12-24 HOURS. 

$$
COBB