December Starts Mild; No Sign of a Stormy Weather Pattern

10pm Sunday…

That storm of flurries in the metro area was fun last night around midnight to 1am.  Lots of us saw a dusting, although no one saw more than 1/2″.  I see some totals up around 2-3″ max in the Gorge.  Not exactly a big snow storm…or even any sort of snow storm.  But a nice little start to the cold season weather fun.  Officially no measurable snow fell in Portland so we haven’t seen our “first snow” yet this season

East wind is still screaming through the western Gorge this evening, gusting 70-80 mph at times at Crown Point.  But tomorrow the high pressure east of the Cascades weakens quite a bit; so the wind dies down too.  That means a bit warmer in the metro area and Gorge too.  Otherwise we should see a fantastic first Monday of December; abundant sunshine and high temperatures near normal.  That’s 45-50 this time of year.

November was very dry, in fact the driest in 26 years in Portland!

Remember October was dry as well.  Just for fun I checked all the October/Novembers with less than 5″ rain in Portland (only 3.03″)  All 5 since 1976 ended up with little/no winter snow in Portland.  The winters following were all generally quite boring in our area. That’s 76-77, 87-88, 93-94, 02-03, 13-14.  That’s not a forecast; I’m just noting that it’s interesting.

What’s ahead?  A mild start to December.  There’s no sign of arctic air or lowland snow.  Check out the ECMWF ensemble forecast of 24 hour snowfall at PDX.  That’s 51 runs of the ECMWF model and not even a hint of snow in the valley through mid-month.

There are hints that we MAY have a wetter pattern arriving, but it’s still 10 days out on the ECMWF…hmmm

The GFS ensembles show the mild weather first half of December

I think the most striking feature is the lack of storminess continuing into early December.  Sure, we had one “bomb cyclone” move into the southern Oregon coastline.  But otherwise it’s been quiet most of the past two months.  There’s quite a bit of a “splitty” look to the upper-level pattern right now and into Tuesday.  See the upper-level low west of California?  It’s “cut off “from the main flow up to our north on Tuesday’s map.  This can tear weather systems apart

An approaching cold trough on Friday appears to be splitting a bit as well

At 10 days out (Wednesday the 11th), the flow is more consolidated, but heights are higher (warmer) than normal.  This would be a wet & warm December pattern.

To summarize:

I don’t see any big weather “events” in the next week that will have any big impact on your life.

Chief Meteorologist Mark Nelsen