December 2020 Weather Observations for the PNW

[SilverFallsAndrew]

Eugene just mixed out and popped to 47.

[Deweydog]

Did the founding fathers predict a cold PNW winter this year?

[MossMan]

Had Christmas breakfast at our 700’ neighbors. The view looking out to Camano island and the Olympics.

[SilverFallsAndrew]

7 minutes ago, Deweydog said:

Did the founding fathers predict a cold PNW winter this year?

No

[Jesse]

12 minutes ago, SilverFallsAndrew said:

Eugene just mixed out and popped to 47.

I

 

 

bet many spots hit 50 tomorrow Andrew.

[Jesse]

1 hour ago, SilverFallsAndrew said:

Some pineapples on this run. 

Omegaraptor should like/hate that.

[Winterdog]

10 minutes ago, MossMan said:

Had Christmas breakfast at our 700’ neighbors. The view looking out to Camano island and the Olympics.

Wow, no snow to be seen at 700 feet.  Our area is still covered in snow with a temp of 39.  Being wind protected is the key!

[TigerWoodsLibido]

29 minutes ago, SilverFallsAndrew said:

Eugene just mixed out and popped to 47.

Weird didn’t even feel much change.

[Brian_in_Leavenworth]

1 hour ago, Timmy_Supercell said:

Spokane sees more snow in a season than my place, have they been relatively quiet lately?

In the AFD they said something about Winter will finally be appearing from Wenatchee to Spokane.

Overall some parts of Eastern WA have had a few snow events, but at times marginal for the lowlands.  For example, I got about 6 or 7 inches on Wednesday the 16th, but from Wenatchee east to Spokane it was pretty much rain. 

And we had rain when the snow happened earlier this week West of the mountains.  Cold air arrived here after the precip left.  So most of Eastern WA has not had much snow. 

With the polar jet pointing at us starting mid next week onward, much of the area will see several chances of snow.

[Rubus Leucodermis]

Now 37˚F after a high of 38. Fourth sub-40˚F high in a row, assuming it doesn’t warm up before midnight.

[TacomaWaWx]

43/35 In Tacoma, 0.28” this evening so far. 

[MossMan]

30 minutes ago, Acer said:

Wow, no snow to be seen at 700 feet.  Our area is still covered in snow with a temp of 39.  Being wind protected is the key!

They still have snow to the left of this pic in their wooded area, much like my place where there is more tree protection. 

[MossMan]

Taking a stroll in the forum time machine to later January 2019 makes me feel a lot better..

[Chewbacca Defense]

12 minutes ago, Rubus Leucodermis said:

Now 37˚F after a high of 38. Fourth sub-40˚F high in a row, assuming it doesn’t warm up before midnight.

We hit 42 over here on this side of town.  Back down to 38 now.

[Gradient Keeper]

If this SSWE is supposed to occur by Day 8-10 shouldn't we begin to see that reflected on the models(ensembles) closer to New Years? Thus far GEFS shows absolutely no changes to Day 16 with a persistent block/positive anomaly over NE Canada.

[Dave]

A cold, wet Christmas turned into a warm, wet Christmas.

[Dave]

My sister that lives in Johnson City, TN got a white Christmas. Currently 18 degrees there.

[OysterPrintout]

9 minutes ago, DJ Droppin said:

If this SSWE is supposed to occur by Day 8-10 shouldn't we begin to see that reflected on the models(ensembles) closer to New Years? Thus far GEFS shows absolutely no changes to Day 16 with a persistent block/positive anomaly over NE Canada.

From my general amateur investigation; while it appears likely to occur, the precise details of what form of PV split/disruption take place are still very much in the air and delayed beyond the initial SSW model reach. Wind reversal isn't progged until the end of the first week of Jan. Lots of details to be ironed out and it is my suspicion that models seem to latch pretty late to these kind of potentially massive shakeups.

[SilverFallsAndrew]

6 minutes ago, dolt said:

My sister that lives in Johnson City, TN got a white Christmas. Currently 18 degrees there.

My kinfolk in Eastern Kentucky also had a white Christmas. 

[AbbyJr]

13 minutes ago, DJ Droppin said:

If this SSWE is supposed to occur by Day 8-10 shouldn't we begin to see that reflected on the models(ensembles) closer to New Years? Thus far GEFS shows absolutely no changes to Day 16 with a persistent block/positive anomaly over NE Canada.

I expect by New Years we will start to see some model changes, assuming the SSW verifies.

[Jesse]

21 minutes ago, MossMan said:

Taking a stroll in the forum time machine to later January 2019 makes me feel a lot better..

Glad that the next month came along and disproved that our climate is warming. Boy did I have egg on my face!

[snow_wizard]

1 hour ago, AbbyJr said:

Was there a SSW event in January 2020? I don't recall there was but there were other factors that led to the arctic blast.

There was.  A big one right around Jan 1.  The good stuff came a couple weeks later.

[AbbyJr]

1 minute ago, snow_wizard said:

There was.  A big one right around Jan 1.  The good stuff came a couple weeks later.

Thats probably what saved our winter given the strong unrelenting vortex. Was it a Siberian or North Atlantic?

[snow_wizard]

For those who want to watch the SSW unfold.  The high latitude stuff is what you want to look at of course.

https://www.cpc.ncep.noaa.gov/products/stratosphere/temperature/

 

[TigerWoodsLibido]

26 minutes ago, dolt said:

A cold, wet Christmas turned into a warm, wet Christmas.

Par for the course. Sometimes we get warm ridging too.

[TigerWoodsLibido]

9 minutes ago, snow_wizard said:

There was.  A big one right around Jan 1.  The good stuff came a couple weeks later.

It was so good we had a high of 49F or more from the 18th-the end of the month.

[snow_wizard]

7 minutes ago, AbbyJr said:

Thats probably what saved our winter given the strong unrelenting vortex. Was it a Siberian or North Atlantic?

I seem to remember it was Siberian. The 2019 SSW came at the same time as our cold wave began.  Maybe there was no vortex to wipe out that time.  It seems to have coincided with the big pattern change though.  It appears the normal lag is a couple of weeks or so.

[AbbyJr]

5 minutes ago, snow_wizard said:

I seem to remember it was Siberian. The 2019 SSW came at the same time as our cold wave began.  Maybe there was no vortex to wipe out that time.  It seems to have coincided with the big pattern change though.  It appears the normal lag is a couple of weeks or so.

Yeah given this SSW has to wipe out the vortex, there will probably be a lag. Thats why I don't anticipate an arctic blast until mid-late January, if one is going occur as a result of the sudden warming event. My guess, though I'm not sure, is that models should start showing signs of a pattern change in the next week or so as the SSW unfolds. Though its possible we could see a sudden model shift after the 7-14 day lag period. There's also unfortunately no guarantees this SSW event will even result in a PNW arctic blast. But we do have ENSO and QBO on our side, so thats encouraging.

[TheNewCulverJosh]

Just a cool microclimate comment here as we wind down our Christmas.  It snowed until we left Culver at 1 PM today, temp 26.0 when we left.  We hung out with some friends in Eagle Creek, west of Redmond, hung around 46 the whole time.  Went to my brothers for an hour after around 4 PM and it was still 46.  We left Redmond around 515 and headed home.  When we got to our turnoff at the Culver hwy, just past Juniper Butte it was still 44.  In the mile and a half it took to get to Culver it dropped to 28 degrees with low clouds and fog, still socked in with snow and icy roads.  Still currently 27.6.  Pretty cool Christmas day. 

[Brian_in_Leavenworth]

Interesting that Pivotal Weather now has the current version of the new GFS V16.  Used to be they only had it for the 0Z runs and you had to wait a day. Maue said there is a 30 day stability test underway, whatever that means

 

[snow_wizard]

26 minutes ago, TigerWoodsLibido said:

It was so good we had a high of 49F or more from the 18th-the end of the month.

It did ok here and very well north of here.

[snow_wizard]

14 minutes ago, Brian_in_Leavenworth said:

Interesting that Pivotal Weather now has the current version of the new GFS V16.  Used to be they only had it for the 0Z runs and you had to wait a day. Maue said there is a 30 day stability test underway, whatever that means

 

It will be interesting to see how good it is.

[snow_wizard]

21 minutes ago, TheNewCulverJosh said:

Just a cool microclimate comment here as we wind down our Christmas.  It snowed until we left Culver at 1 PM today, temp 26.0 when we left.  We hung out with some friends in Eagle Creek, west of Redmond, hung around 46 the whole time.  Went to my brothers for an hour after around 4 PM and it was still 46.  We left Redmond around 515 and headed home.  When we got to our turnoff at the Culver hwy, just past Juniper Butte it was still 44.  In the mile and a half it took to get to Culver it dropped to 28 degrees with low clouds and fog, still socked in with snow and icy roads.  Still currently 27.6.  Pretty cool Christmas day. 

Something must trap the cold air there.  Pretty neat how tightly confined some microclimates can be.

[TigerWoodsLibido]

3 minutes ago, snow_wizard said:

It did ok here and very well north of here.

My point was it left a lot to be desired regionally.

[TT-SEA]

ECMWF was wrong... no Christmas snow here as it showed.    All rain.  Gray on the map usually means nothing.

[snow_wizard]

11 minutes ago, TigerWoodsLibido said:

My point was it left a lot to be desired regionally.

The pattern reacted to the SSW, but the details didn't work out well for areas more south.  Every event is different as you know.

[TigerWoodsLibido]

3 minutes ago, snow_wizard said:

The pattern reacted to the SSW, but the details didn't work out well for areas more south.  Every event is different as you know.

Sure would have been nice if we could have noticed any appreciable difference to the pattern down this way. SSWs don't make a lick of difference in terms of meaningful cold and snow this far south. Feb 2019 was luck.

[MossMan]

20 minutes ago, snow_wizard said:

It did ok here and very well north of here.

I had 19 degree heavy snow falling at one point during that event. 

[Phil]

4 minutes ago, TigerWoodsLibido said:

Sure would have been nice if we could have noticed any appreciable difference to the pattern down this way. SSWs don't make a lick of difference in terms of meaningful cold and snow this far south. Feb 2019 was luck.

Hmm..I’m not sure I agree with that. The effects can vary wildly but they’re not latitude dependent as far as I know.

[Phil]

On 12/24/2020 at 11:09 AM, TT-SEA said:

 

 

This map is better.