Seattle weather: The big warm-up will stick

What a difference a week in weather makes! A week ago, Western Washington was still in a deep freeze. Now, it feels almost balmy outside.

Last week, it took several days to erode the sub-freezing air as milder air moved onshore from the Pacific. Some sheltered locations or areas still exposed to winds with colder air blowing in from Eastern Washington and the interior of Western Canada resulted in lingering snow or freezing rain.

But now, all of Western Washington has warmed up and will remain that way this week. Westerly flow from the Pacific is expected to bring a series of weather systems onshore with rain at times and temperatures a little above mid-January averages. Highs will hover around 50 degrees all week, the warmest since early in the month with lows only ranging from the upper 30s to the mid-40s.

In the mountains, periods of rain and snow will continue throughout the week with snow levels ranging from 4000 to 5000 feet. Yet, colder air from the eastern half of the state is expected to seep westward through the passes and retain a mix of rain and snow until mid week.

The SMN Interviews: Jancee Dunn, Matt Markovich, Herb Weisbaum

Heading into this month, the mountain snowpack was well below average ranging from about 30 to 60 percent of average. The recent snows in the mountains helped make up some of that deficit. The snowpack in the Olympics and Cascades now stands about 45 to 90 percent of average, depending on the location.

The latest seasonal weather outlook released late last week maintains good odds on warmer and wetter than average conditions for the rest of this winter season through March. Warmer than average temperatures usually means a higher mountain snow level than average – not the best news for building that snowpack.

The milder wet weather offers a silver lining. At least heating bills should be lower than they were during the cold snap.