Winter 2011-2012: 4th Warmest Across USA! Dry in Northwest

March 7, 2012

It wasn’t a “warm” winter here in the Pacific Northwest, but the rest of the country was roasting…well, in a winter sort of way.  It was the 4th warmest winter on record across the USA!  Here’s a chart showing statewide rankings.  Note that 117  is the warmest winter ever recorded in a state and 1 is the coldest winter on record.  Also note how many Midwest states were in the top 2-10 warmest winters.  I doubt they complain about that in such a cold climate!

We were reasonable close to normal here in the Pacific Northwest, with Washington the only state showing below normal temps for the winter period.  By the way, yes, I know technically winter goes until the Spring Equinox in a couple of weeks.  Meteorologists/climatologists define winter in the Northern Hemisphere as the 3 coldest months (December, January, and February). 

Here is the precipitation for the same period:

This map says we’ve had quite a dry winter throughout most of the West.  That’s true for December-February, BUT, for the purposes of water supply and snowpack, November-March is really the important period.  So let’s just take November-February precipitation…sorry, no pretty map this time:

Still the driest “wet season” in the Pacific Northwest in 7 years. Hopefully the next 7-10 days (looking very wet!) will make up for some of that in the mountains.  There have only been 3 drier seasons (so far) since the big 1976 drought year.  This would be due to the endless weeks of no precipitation in December, January, and early February.  That plus these westerly flow setups are horrible for getting precipitation east of the Cascades.  Northern Oregon and Washington have fared okay, on the edge of much heavier precipitation several times; but go south to the Central/Southern Oregon Cascades and east of Central Oregon to find well below average snowpacks.

Where do we go from here?  A ton of rain coming up…check out the WRF-GFS forecast of 3 day rain from Sunday afternoon through Wednesday afternoon next week:

This is a “Cascadia-Level” rainy period!  A big soaking next week from Northern California all the way to Central BC.  All westside mountains are in the 2-5″ range, much of that as snow.  Snow levels will be in the 1,500-4,000′ range from Sunday-Thursday.  Lowest snow level is Sunday night and Monday morning.  Not quite as cold as what we’ve seen lately plus a gusty southwest wind the whole time so I’m not real fired up about it.

Looking for Spring weather?  You have one day.  Tomorrow is the only day with perfect offshore flow (east wind), a much warmer air mass, and sunny or mostly sunny all day.

Chief Meteorologist Mark Nelsen