000
AXPZ20 KNHC 072208
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC FRI DEC 07 2007

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN
FROM THE EQUATOR TO 32N...EAST OF 140W. 

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2130 UTC.
 
...ITCZ...
INTERTROPICAL CONVERGENCE ZONE AXIS ALONG 7N78W 9N90W 12N113W 
8N140W. NO SIGNIFICANT CONVECTION NOTED.

...DISCUSSION...
BROAD PATTERN IN PLACE WITH A TROUGH DOMINATING MOST OF THE 
AREA W OF 100W. UPSTREAM MID TO UPPER LEVEL RIDGE WITH AXIS 
ALONG 144W APPEARS TO BE AMPLIFYING WITH TIME. SEVERAL WEAK 
UPPER LEVEL CYCLONIC CIRCULATIONS WERE EMBEDDED WITHIN THE 
TROUGH NEAR 23N117W AND 14N128W. A STRONG UPPER LEVEL 
REINFORCING TROUGH IS DIGGING SWD ALONG THE CALIFORNIA 
COAST AND EXTENDS SWWD TO NEAR 29N132W AND WAS ACCOMPANIED BY 
STRONG UPPER LEVEL SUBSIDENCE IN ITS WAKE. AS THIS UPPER TROUGH 
PUSHES EWD INTO THE ROCKIES THROUGH SAT...THE CUTOFF LOW NEAR 
23N117W WILL CONTINUE TO OPEN UP AND ACCELERATE OUT TO THE NE  
INTO THE SOUTHWEST U.S. A COLD FRONT ASSOCIATED WITH THE UPPER 
TROUGH IS MOVING INTO THE NORTHERN WATERS OFF THE BAJA COAST 
ALONG 32N118W 27N130W 28N136W AND WAS USHERING IN FRESH NLY FLOW 
AND LARGE SWELL. MEANWHILE...SLY FLOW ON THE EAST SIDE OF THE 
CUTOFF LOW NEAR BAJA IS SUSTAINING A WEAK SURFACE TROUGH THROUGH 
THE ITCZ ALONG ROUGHLY 112W. THIS IS ALSO DRAWING MOISTURE NWD 
SUPPORTING ISOLATED SHOWERS NEAR THE TROUGH. AS FAR AS SEAS 
GO...SHIPS REPORT MODERATE LARGE NLY SWELL ACROSS MOST OF THE 
DISCUSSION AREA THIS MORNING. TRENDS SHOW THE SWELL DECAYING 
BELOW 8 FT THROUGH TODAY IN ALL BUT THE AREA N OF 25N.

FOR THE WEEKEND AHEAD...THE RIDGE WILL BUILD ALONG ROUGHLY 
135W...AS THE TROUGH DEEPENS OVER THE SOUTHWEST U.S. THIS WILL 
TIGHTEN THE GRADIENT OFF THE CALIFORNIA COAST...WITH NLY WINDS 
PICKING UP AS FAR SOUTH AS 23N W OF BAJA CALIFORNIA. THIS WILL 
USHER IN A NEW ROUND OF LARGE NLY SWELL TO START TO PUSH 
INTO THE WATERS W OF NRN BAJA BY SUN. IN ADDITION...THE BUILDING 
RIDGE STRENGTHENS THE SURFACE HIGH NW OF THE AREA...WHICH IN 
TURN ENHANCES TRADE WIND FLOW. FURTHER E...STRONGER ELY FLOW 
THIS WEEKEND OVER THE CARIBBEAN WILL PROMOTE FRESH ELY FLOW 
THROUGH THE GULF OF PAPAGAYO STARTING TOMORROW. A SURGE OF SLY 
FLOW S OF THE EQUATOR WILL INCREASE WINDS AND SEAS TO THE WEST 
OF THE GALAPAGOS SUN.

$$
COBB