Forecast doesn't show much improvement for Thanksgiving

Our trial by ice is not over.

In fact, Wednesday morning's weather is likely to be colder than we've experienced — even into single digits in some places. And driving still could be a challenge on Thanksgiving Day, according to the National Weather Service.

Meteorologist Allen Kam said there's a "very slight chance of snow" early Wednesday in coastal areas. Temperatures should "warm up" into the 20s by afternoon and evening.

Freezing temperatures are expected through midday Thanksgiving, when a weak warm front should return temperatures to normal, according to the weather service. Snow is possible early Thursday or rain later in the day.

"Our computer models have not yet settled on when the precipitation will begin," Kam said. "Whatever we get will be light."

Temperatures are expected to remain above freezing through the weekend, when showers also are likely.

While Seattle-area residents can expect a relatively warmer weekend, many still are looking backward to Monday's storm, which crippled much of the region.

The National Weather Service gives itself a passing grade for its forecasts of recent days — including giving enough notice of Monday's weather.

"The forecast wasn't the problem," University of Washington meteorologist Cliff Mass said.

The snow intensified a bit earlier than predicted, and accumulations were a tad higher than the morning advisory anticipated.

But those are nitpicks.

"I think we did a very good job," said Brad Colman, meteorologist-in-charge for the weather service. "You probably could not expect better."

The first heads-up was issued more than a week in advance. Starting last Wednesday, meteorologists laid out the range of possibilities in daily briefings for up to 100 government, utility and business officials.

An unanswered question was whether the bulk of the snow would veer south and miss the metropolitan area. Relying on his and other computer models, that's what Mass was betting on as late as Sunday morning, and what he posted on his blog.

None of the models did a good job of picking up on the threat of snow, Colman said.

But weather-service meteorologists, drawing on their combined 250 years forecasting experience, did. Sunday's forecast called for 1-3 inches across the metropolitan area. By 9 a.m. Monday, that was upgraded to 2-6 inches, pretty much what fell.

"We were sweating bullets," Colman said. "It was a demonstration of how human forecasting can be a really important part of the process."

Sandi Doughton: 206-464-2491 or sdoughton@seattletimes.com