DELIVERY OF SNOW ON MENU; OFFICIALS ENCOURAGE DRIVERS TO PREPARE.

Byline: David Bloom Daily News Staff Writer

Plan ahead.

If you're heading north out of town for Thanksgiving, the National Weather Service has a chilly warning: A storm predicted to hit the Los Angeles area today could dump up to 8 inches of snow at levels low enough to snarl the two main mountain passes north.

``The Grapevine is at 4,200 feet (elevation) and Cajon Pass is at 3,800. That's right about the level the snow will reach,'' said Stewart Seto of the National Weather Service station in Oxnard.

``Drivers should be prepared. If they could stay home and have Thanksgiving with their families, it could be better.''

Even stay-at-home celebrants are facing a soggy Turkey Day's eve, with as much as an inch of rain expected to fall through midday Thursday, along with 25 mph wind gusts, high surf and overnight temperatures as chilly as 40 degrees, Seto said.

Daytime temperatures won't do much to thaw a frozen turkey, edging no higher than the mid-60s throughout the region, Seto said.

Thunderstorms and even waterspouts also are considered likely for the storm system, the strength of which will be determined by how much moisture it pulls from two wet systems out of the Hawaiian islands, Seto said.

The weather will provide good news for skiers, however, with as much as a foot of snow expected to fall at the higher elevations, Seto said.

The front should begin to clear out by Thursday night, with partly cloudy skies projected for Friday, and mostly sunny days welcoming early Christmas shoppers Saturday, Seto said.