000
AXPZ20 KNHC 100915
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC MON DEC 10 2007

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

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0845 UTC.
 
...ITCZ...
INTERTROPICAL CONVERGENCE ZONE AXIS ALONG 7N78W 9N91W 8N101W 
8N111W 7N118W 9N140W. ISOLATED MODERATE CONVECTION NEAR 7N78W 
9N96W 9N102W AND 10N109W. 

...DISCUSSION...

DEEP POOL OF COLD AIR IN THE UPPER ATMOSPHERE HAS CONTINUED TO 
DROP SWD TONIGHT TO NEAR 29N118W. STRONG JETSTREAM DIVING S 
ALONG 120W STILL CARVING OUT MID LEVEL TROUGH TO 15N. SUBTROPIC 
JETSTREAM FROM 15N115W NE TO NW MEXICO. MID LEVEL RIDGE STILL 
ALONG 140W EXTENDS N TO GULF OF ALASKA WHICH IS HELPING SUPPLY 
STRONG NLY FLOW ALOFT ALONG 125W. ON THE SURFACE TONIGHT WEAK 
LOW PRES CENTER NEAR 29N114W WITH TROUGH EXTENDING S TO 18N113W. 
PACIFIC RIDGE ALONG 135W EXTENDS SE OVER REGION TO 16N116W 
PRODUCING NE TRADES 20 TO 25 KT FROM 12N TO 24N W OF 125W AND A 
NLY WIND OF 20 TO 25 KT BETWEEN 120W AND 128W WITH NLY SWELL TO 
13 FT. GAP WINDS ARE MOSTLY LIGHT EXCEPT FOR PAPAGAYO WHERE SSMI 
SHOWS WINDS TO 20 KT. CROSS EQUATORIAL SLY WINDS TO 20 KT S OF 
5N E OF 110W AND SE WINDS TO 20 KT S OF 5N W OF 130W.

LATER DAY 1 STRONG CLOSED OFF MID LEVEL CYCLONIC CENTER BEGINS 
TO LIFT NE TO 27N115W. MID LEVEL RIDGE ALONG 140W BEGINS TO 
WEAKEN AND SHIFT EWD SLOWLY AS NEXT STRONG TROUGH APPROACHES 
FROM THE NW. ON THE SURFACE LATER DAY 1 WEAK LOW PRES MOVES 
INLAND OVER NW MEXICO RELAXING GRADIENT W OF BAJA THUS NW WINDS 
DECREASE TO 15 KT. PACIFIC RIDGE WEAKENS SLIGHTLY AS MID LEVEL 
RIDGE WEAKENS..THUS NE TRADES MOSTLY 20 KT. GAP WINDS CHANGE 
LITTLE WITH ELY FLOW THROUGH PAPAGAYO 20 KT. CROSS EQUATORIAL 
SLY WINDS WEAKEN TO 10 TO 15 KT.

FOR DAY 2 GFS MODEL SHOWS NEW SURGE OF COLD AIR DROPPING SWD 
ALONG 116W. OLD POOL OF COLD AIR LIFTS NE OVER SW CONUS. MID 
LEVEL RIDGE REMAINS STATIONARY NEAR 30N142W. WEAK DISTUBANCE AT 
MID LEVELS NEAR 10N108W MOVING SLOWLY NE. ON THE SURFACE DAY 2 
WEAK TROUGH OF LOW PRES CONTINUES ALONG 117W THUS WINDS ALONG 
THE BAJA COAST N OF 26N SWLY 10 KT AND S OF 25N NELY 10 KT. 
PACIFIC RIDGE REMAINS STATIONARY BUT WEAKENS. NE TRADES OF 20 KT 
CONFINED TO AREA BETWEEN 10N AND 20N W OF 120W. MODEL SHOWS WEAK 
SURFACE LOW NEAR 10N108W WHERE MID LEVEL DISTURBANCE IS LOCATED. 
MODEL COULD BE OVERDOING THIS SYSTEM. GAP WINDS ALONG CENTRAL 
AMERICAN COAST NE TO E 20 KT WITH LARGE HIGH OVER SW ATLC. CROSS 
EQUATORIAL SLY WINDS TO 20 KT BETWEEN 100W AND 110W ENHANCED BY 
LOW CENTER NEAR 10N108W. 

$$
RRG