January: Coldest Month Since My High School Years

January 29, 2017

11pm Sunday…

Since we only have 2 days left this month we have a pretty good idea where January will end up in the history books

markjanuarycoldmonthpdx

As of tonight, the 33.2 degree average temperature makes January 2017 the coldest month in Portland since December 1985!  That was halfway through my junior year in high school…a long time ago in a county far, far (80 miles) away.  That month we had high pressure centered over the Pacific Northwest much of the month with snow-covered terrain east of the Cascades the whole time.  Cold east wind blew much of the month through the Gorge…sound familiar?

This will also be the 7th or 8th coldest month on record at PDX.  Those airport weather records go back to 1939.

What’s Ahead?

It appears we have one more brush with cold/snow/ice this week as February arrives.    Once again the Alaska upper-level ridge is trying to rise again.  It did that in early/mid December and early/mid January.  That shoves cold air to its east (over Western Canada) to the south toward and into the Pacific Northwest.  There will be a “conflict zone” in the Pacific Northwest where the colder air from the north moves down under milder/moist air above.  That “zone” seems to want to hang out somewhere near the Oregon/Washington border Wednesday through Friday according to most models.

I’m VERY confident we have a chilly east wind back in the Gorge and east metro Wednesday-Friday.  I’m FAR LESS confident about the depth & intensity of the cold air and how much moisture rides over it Wednesday-Friday.  For that reason I have very few details for now.

marksnowsetup2_coldfromeast

This is just a brief posting to answer a few basic questions; of course I’ll have lots more details in the next few days

HIGHLIGHTS

  • As of this moment I think we’re “safe” from any travel issues west of the Cascades (due to snow/ice) through Wednesday afternoon at least.
  • Wednesday-Friday will be a cold three days with a gusty east wind blowing in the usual Gorge and Gorge-influenced areas (you know who you are!)
  • Most models have very little moisture available for snow or freezing rain west of the Cascades until at least sometime Thursday or Thursday evening.
  • There is no need to cancel plans or have any sort of “grocery-store freak out” tomorrow or Tuesday.
  • Everything points to quite a bit of warming next weekend west of the Cascades with very mild weather next week, we are not entering a many days-long freeze
  • The airmass moving into our area is not as cold as the one over us the first half of January
  • If you live in the Gorge (especially central/east) it’s very likely another snow/ice episode is coming at some point Wednesday night-Saturday.  Temps near/below freezing during that time.

 

Maybe most important, as of now I don’t see a similar setup for a road fiasco like early January.  By that I mean the failure of local transportation agencies to clear roads of solid snow/ice well after the event.  This isn’t a “snow, then hard freeze for a bunch of days” setup like the first half of January.  Even if we get snow/ice it will go away within a short time (hours to a day or two).

Stay tuned!

Chief Meteorologist Mark Nelsen