December 2020 Weather Observations for the PNW

[mtep]

4 hours ago, Rubus Leucodermis said:

Pics from Anderson Mountain. It did not feel warmer than 30°F at 3,000 feet, where I turned around, and was probably more like 28°F there.

I sometimes camp here. Toyed with the idea of doing a overnight, but decided against it. Just as well, as it enabled me to chicken out and park my 2WD truck before the road got icy. Didn’t feel like putting chains on.

 

What things looked like at 3,000 feet elevation, where I turned around.

 

View from 3,000 feet.

 

View from 2,000 feet, where I parked.

 

Inversions starting to form near Alger.

Awesome pics. How's the road right now? I've been tempted to take my impreza up there before the gate closes for the season but not sure if i'll have clearance issues.

[Rubus Leucodermis]

1 minute ago, mtep said:

Awesome pics. How's the road right now? I've been tempted to take my impreza up there before the gate closes for the season but not sure if i'll have clearance issues.

So far as ground clearance issues, the road is just fine. Any car should be able to make it. Starts getting icy at around 2,000 feet.

[SilverFallsAndrew]

As DJ mentioned. The GEFS is better than the operational it seems. 

[Jesse]

44/34 day here. Mostly sunny early with overcast conditions and strong East winds starting by later in the day.

41 degrees, tree is up and watching Muppets Christmas Carol currently.

[Gradient Keeper]

2 minutes ago, SilverFallsAndrew said:

As DJ mentioned. The GEFS is better than the operational it seems. 

Both the GEFS and CMCE consistently show Day 9-10+ the jet dies and retracts near/west of ~180 W/dateline. Good things ahead.

[Jesse]

3 minutes ago, SilverFallsAndrew said:

As DJ mentioned. The GEFS is better than the operational it seems. 

Have you ever seen Muppets Christmas Carol Andrew 

[TigerWoodsLibido]

1 minute ago, Jesse said:

Have you ever seen Muppets Christmas Carol Andrew 

He’s associating you with a 2x Oscar winner Andrew.

[SilverFallsAndrew]

25 minutes ago, Jesse said:

Have you ever seen Muppets Christmas Carol Andrew 

Love it. 

[Meatyorologist]

The 00z GFS teased at some snowflakes on the higher hills the night of the 21st. Not completely unrealistically far out.

[Brian_in_Leavenworth]

Just looking at trying to compare the EPS to the last ECMWF weeklies, using PNA as a comparison.  The 0Z is not out yet, but probably similar.

A few observations.  Both have the PNA going up and down between the 14th and 25th, then down.  Up a bit around the 14th, down a bit around the 16th, up around the 18th, down about the 21st.  Then  up heading toward Christmas, and then down after that.  Current models go to just about the 26th or so, and of course the Weeklies go way past that.  But my point is that, what we are seeing with the EPS is pretty consistent with what we saw out of the weeklies a few days ago.  I think that is a good thing.

 

[SilverFallsAndrew]

I saw a Muppets Christmas Carol twice in theaters. 92-93 was easily the best winter of my life. SLE had 32” of snow that season. 

[Meatyorologist]

2 minutes ago, Brian_in_Leavenworth said:

Just looking at trying to compare the EPS to the last ECMWF weeklies, using PNA as a comparison.  The 0Z is not out yet, but probably similar.

A few observations.  Both have the PNA going up and down between the 14th and 25th, then down.  Up a bit around the 14th, down a bit around the 16th, up around the 18th, down about the 21st.  Then  up heading toward Christmas, and then down after that.  Current models go to just about the 26th or so, and of course the Weeklies go way past that.  But my point is that, what we are seeing with the EPS is pretty consistent with what we saw out of the weeklies a few days ago.  I think that is a good thing.

 

Yeah, there's no doubt that we will enter a period of high latitude blocking, with average heights rising dramatically over the northern Pacific, consequentially lowering the PNA. The real questions are,

1. How favorable will the block positions be?

2. How much cold air will be available to us from the north? (A.K.A. Will ridging beforehand usher in mild Pacific air into inland BC and the Yukon?)

Statistically speaking, a pattern with an increased bias towards blocking, along with La Niña and +QBO, for an extended period of time, increases the odds of a PNW cold snap drastically, perhaps by as much as 80-90%. But it is far from a guarantee at this point, especially given the solutions we've seen from the OP runs.

It is hard to snow down to sea level here. There is much room for things to go wrong, and not very much room for things to go right. Even under an extreme cold pattern, moisture can be an issue (ex. north of Portland during 2016-17.) I'd reserve excitement and calls for guaranteed snow down here until a few days out, at most. But there are many reasons to be hopeful. Odds are the highest in the country at this latitude that we'll be colder than normal in January. Stay hopeful y'all, and be patient.

06z in around an hour and a half (d*** this evening is going by slowly...)

[Meatyorologist]

Also sorry, @Brian_in_Leavenworth for using my reply to write an essay.  I guess I had a few things on my mind.

[Gradient Keeper]

Temp 37.7, Dewpoint 31.8, with moderate rain and gusty east winds.

[Gradient Keeper]

1 hour ago, Brian_in_Leavenworth said:

Just looking at trying to compare the EPS to the last ECMWF weeklies, using PNA as a comparison.  The 0Z is not out yet, but probably similar.

A few observations.  Both have the PNA going up and down between the 14th and 25th, then down.  Up a bit around the 14th, down a bit around the 16th, up around the 18th, down about the 21st.  Then  up heading toward Christmas, and then down after that.  Current models go to just about the 26th or so, and of course the Weeklies go way past that.  But my point is that, what we are seeing with the EPS is pretty consistent with what we saw out of the weeklies a few days ago.  I think that is a good thing.

 

This is really good, solid analysis. Thanks. This looks mighty promising as we head past Christmas which is also when the GEFS and CMCE turn mighty blocky. C'MON!!!!

[Meatyorologist]

06z GFS Init.

[Meatyorologist]

06z GFS Day 1

[Meatyorologist]

06z GFS Day 2

[Meatyorologist]

06z GFS Day 3

[Meatyorologist]

06z GFS Day 4

[Meatyorologist]

06z GFS Day 5

[Meatyorologist]

06z GFS Day 6

[Meatyorologist]

06z GFS Day 7

[Meatyorologist]

06z GFS Day 8

[Meatyorologist]

06z GFS Day 9

Blustery storm coming onshore.

[Meatyorologist]

06z GFS Day 10

[Meatyorologist]

06z GFS 10 Day Precip/Snowfall

[Meatyorologist]

06z GFS Day 11

[TigerWoodsLibido]

Thanks for posting!! Lots of mtn snow at least.

[TigerWoodsLibido]

[Gradient Keeper]

Temp 36.6, Dewpoint 33, with light rain and very gusty east winds continuing. I might drop to 36, but due to rising dewpoints and exhausting available wet bulb cooling I won't get any colder than that.

[Meatyorologist]

Early amateur-ish look shows an improving pattern in these last frames as a deep trough digs into SE Asia w/ associated wavedriving producing a solid block upstream in an ideal position.

[Meatyorologist]

06z GFS Day 12

[Meatyorologist]

Might just default to North Pacific view after D10. Much more information present (plus it allows point-and-click soundings in that view mode, so a lot more information there.)

[Gradient Keeper]

1 minute ago, Meatyorologist said:

06z GFS Day 12

Now that's not bad. Let's move that to Day 4.

12z GFS in 4 hours 43 minutes

[Meatyorologist]

06z GFS Day 13

There is a *slight* possibility this taps into that extreme polar air to the north. Worth watching.

[Meatyorologist]

Aaaaand we're off. This block is blowing up like a bomb.

[Meatyorologist]

06z GFS Day 14

[Meatyorologist]

06z GFS Day 15

This is a beautiful pattern.

[Gradient Keeper]

Thanks @Meatyorologist for posting the 6z. Nice block, just need it about 600 miles further east.