000
AXPZ20 KNHC 090348
TWDEP 

TROPICAL WEATHER DISCUSSION    
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC SAT DEC 09 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0345 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG...5N77W 7N85W 5N100W 8N125W 7N140W. 
SCATTERED MODERATE ISOLATED STRONG WITHIN 90-120 NM N OF AXIS 
BETWEEN 125W AND 138W. 

...DISCUSSION...

W OF 100W...
OVERALL PATTERN REMAINS AMPLIFIED WITH A RIDGE BETWEEN TWO  
TROUGHS MAINLY ACROSS THE NORTHERN PORTIONS OF THE AREA. FIRST 
MID-UPPER LEVEL TROUGH EXTENDS FROM A CYCLONIC CIRCULATION JUST 
OFF THE CALIFORNIA COAST NEAR 43N126W SSEWD THROUGH 30N118W THEN 
SWWD TO 24N134W. THIS TROUGH HAS FRACTURED LEAVING A PAIR OF 
UPPER LEVEL CYCLONIC CIRCULATIONS BEHIND IN THE TROPICS NEAR 
18N137W AND 15N144W. ANOTHER MID/UPPER LEVEL TROUGH EXTENDED 
FROM A 4-5 DEG DIAMETER MID/UPPER LEVEL CYCLONIC CIRCULATION 
OVER NRN MEXICO NEAR 28N105W THROUGH 20N106W TO 14N108W. STRONG 
UPPER LEVEL SUBSIDENCE WAS INDICATED IN THE WAKE OF THIS TROUGH 
GENERALLY ALONG THE W COAST OF MEXICO. AN ADDITIONAL AREA OF 
STRONG SUBSIDENCE WAS NOTED N OF 23N BETWEEN 115W AND 128W...
APPROACHING THE W COAST OF BAJA CALIFORNIA. ABUNDANT MID/UPPER 
LEVEL MOISTURE IN THE FORM OF BROKEN TO SCATTERED HIGH CLOUDS 
STREAMING EAST-NORTHEAST COVER THE AREA TO THE EAST AND SOUTH OF 
BOTH TROUGHS SOUTH TO 8N. MID/UPPER LEVEL RIDGING COVERS THE 
AREA BETWEEN BOTH TROUGHS WITH MEAN RIDGE AXIS EXTENDING FROM A 
MID/UPPER LEVEL ANTICYCLONIC CIRCULATION NEAR 12N119W 
NORTH-NORTHEASTWARD THROUGH 25N117W AND TO A CREST WELL NORTH OF 
THE REGION OVER THE FOUR CORNERS REGION OF THE CONUS. ANOTHER 
RIDGE AXIS EXTENDED NWWD THROUGH 22N128W TO 30N130W. DIFFLUENT 
FLOW PATTERN EXISTED BETWEEN THE RIDGE AND THE TROPICAL UPPER 
LEVEL CYCLONIC CIRCULATIONS WAS ENHANCING ITCZ CONVECTION 
BETWEEN 125W AND 138W. AT THE SURFACE...A COLD FRONT EXTENDS 
FROM 32N123W TO 25N127W. NORTHWEST WINDS HAVE DECREASED BEHIND 
THE FRONT TO GENERALLY 20-25 KT MAINLY N OF 28N. HOWEVER...THE 
MAIN PROBLEM AFFECTING THE REGION WITH RESPECT TO THE FRONT ARE 
THE VERY LARGE NW-N SWELLS THAT WILL BE SPREADING THROUGHOUT 
MUCH OF THE WESTERN AND CENTRAL SECTIONS OF THE DISCUSSION AREA 
OVER THE NEXT FEW DAYS AS THE FRONT WEAKENS AND DISSIPATES. 
WAVEWATCH MODEL CONTINUES TO SUGGESTS MAXIMUM HEIGHTS OF 22-24 
FT MOVING INTO THE NORTHWEST PART OF THE AREA IN THE WAKE OF THE 
FRONT. A NEW COLD FRONT BRUSHES THE NORTHERN SECTION OF THE 
REGION FROM FRIDAY EVENING THROUGH SUNDAY BEFORE QUICKLY 
WEAKENING AS IT MOVES INTO SOUTHERN CALIFORNIA AND NORTHERN BAJA 
CALIFORNIA. THIS WILL PROVIDE ANOTHER SHOT OF LARGE SWELLS INTO 
THE AREA THOUGH NOT AS LARGE AS SEEN WITH THE FIRST FRONT.

E OF 100W...
MID/UPPER LEVEL ANTICYCLONE NEAR 10N93W AND ASSOCIATED RIDGING 
DOMINATED THE PACIFIC E OF 100W AND WAS CHARACTERIZED BY AN AREA 
OF STRONG SUBSIDENCE. THIS AREA OF SUBSIDENCE WAS LIMITING 
CONVECTION ALONG THE ITCZ E OF 100W. 

GAP WINDS...
A SHIP WITH CALL SIGN V2AF4 LOCATED NEAR 14.5N95W OR 90 NM FROM 
THE ENTRANCE TO THE GULF OF TEHUANTEPEC REPORTED 35 KT WINDS 
AT 0000 UTC. THIS VERIFIES THE MINIMAL GALE EVENT CONTINUES OVER 
THE AREA WITH N TO NE WINDS OF 30-35 KT IN THE AREA. WINDS 
SHOULD DECREASE TO LESS THAN GALE FORCE BY 36 HOURS OR SO.

NE WINDS OF 20 KT ACROSS THE GULF OF PAPAGAYO WEST TO 89W ARE 
EXPECTED TO CONTINUE THROUGH THE NEXT 48 HOURS THEN DIMINISH TO 
LESS THAN 20 KT.

$$
COBB