DRY PLUS WET EQUALS ... SNOW?

Byline: Greg Bolt The Register-Guard

Today could see the return of the 1-inch winter wonder.

That's about how much snow is supposed to fall in the lower elevations of Lane County today, starting any time this morning. Not really snowman-making snow, but enough to put a winter coat on things.

It's fairly typical for January: A dry, Arctic air mass cruising down from Alaska meets a wet, continental air mass over the Northwest, dropping snow for a few hours when the two overlap. Then it's just dry and cold.

"It's a pretty quick-moving front," National Weather Service meteorologist Jonathan Wolfe said. "But the big thing with this is there's a lot of cold air behind it."

It doesn't take much moisture to produce snow. Wolfe said it only takes a tenth of an inch of moisture to lay down about 3 inches of snow, which is about what's expected in the northern Willamette Valley and at the higher elevations of Lane County.

That means it wouldn't take too much wet to make a lot of white, and how much snow the Eugene-Springfield area will get depends on how much moisture is left when the front gets here and how long the cold air/wet air transition zone spends in the neighborhood.

Once the snow zone has passed, much more wintry temperatures than the mid-50s of recent days are expected. Wolfe said lows in the south valley won't be much above the teens, with daytime temperatures in the low to mid-30s.

That means we'll probably be warmer than we were on Halloween, when the thermometer dropped to an unseasonably low 17. And we could face another flurry or two on Saturday.

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