December 2020 Weather Observations for the PNW

[MossMan]

7 minutes ago, ShawniganLake said:

Wet bulb!

This was moments before the first flakes began to fall that kicked off the epic run that was February-March 2019...Might not see another February setup like that again in my lifetime. 

[TigerWoodsLibido]

Watched this yesterday

 

[Omegaraptor]

Clear skies to the west and clouds to the east.

Tri-Cities stuck in an inversion with freezing fog. Might not break freezing there today. https://www.wrh.noaa.gov/mesowest/getobext.php?wfo=pdt&sid=KPSC&num=72&raw=0

Also, the 5 minute obs are back. 

[TigerWoodsLibido]

Up to 46F with some high clouds.

[Brian_in_Leavenworth]

Early look at the Euro weeklies.  These are 5 day running averages, so it will look a little different than maps that post the anomalies for that particular day.

 

[SilverFallsAndrew]

7 minutes ago, Brian_in_Leavenworth said:

Early look at the Euro weeklies.  These are 5 day running averages, so it will look a little different than maps that post the anomalies for that particular day.

 

I remember the 850mb maps from the previous incarnation of the weeklies better. How does this one compare to the previous run? 

[Brian_in_Leavenworth]

1 minute ago, SilverFallsAndrew said:

I remember the 850mb maps from the previous incarnation of the weeklies better. How does this one compare to the previous run? 

Not as good as the one from Monday.    Not quite as cold, and not quite as wet.    Doesn't look like a major change overall from the Monday run though.   Same general theme, just not quite as good.  At least that is the way I see it.

[TacomaWaWx]

31 minutes ago, MossMan said:

This was moments before the first flakes began to fall that kicked off the epic run that was February-March 2019...Might not see another February setup like that again in my lifetime. 

We may not see a set up like that one again in any month for awhile...especially for the month of February it was incredible. This was February 3rd at 2pm watching the first snow bands work southward! 

[Weather1011]

2 hours ago, Phil said:

Well not consciously..our vehicles had already made contact briefly and were heading towards the divider at 80mph in the pouring rain, before I kind of forced my way through him and back onto the road. It happened so fast. A wreck of some kind was almost inevitable already. But I feel guilty as hell either way. If there is a hell, I’m probably headed there.

FWIW, it was a neutral-fault accident. We were both ticketed for negligent driving, and I was given another ticket for passing on the shoulder (or trying to do so).

Ah, I see. Crazy.

[Brian_in_Leavenworth]

Just looked at the weeklies snowfall totals.  No huge changes, but Bellingham gets a fair amount more on this run than before.  Other areas in Western WA/OR get just a bit less.  My area gets a bit more, but guessing that is more to do with the 3 days this week being replaced by 3 days in January (end of the run).  

And just checked the precipitation charts.  Considering 3 dry days this week are being replaced with 3 days in January which may or may not be wet, I don't see any substantial changes in precip.  Why Bellingham gets a fair amount more of snow than other areas may be because cold air doesn't make it as far south in general.  Just a guess

[Brian_in_Leavenworth]

3 minutes ago, hawkstwelve said:

Latest ECMWF weeklies actually look a hair better near Christmas time, IMO.

Less ridging shown over the west coast and a little stronger signal for a ridge where it matters.

Thanks.  I wasn't looking as much at timing as you were, so that is helpful.

[ShawniganLake]

^ those maps look cold up north.  Where’s a ridge pushing up into Alaska?  

[SilverFallsAndrew]

Thanks for all the info on the weeklies. Maybe still some goods coming up by the end of the month!

[Deweydog]

What happens if next week’s weeklies look better or worse than this week’s weeklies.  Will the weaker week’s weeklies be thrown out in order to defer to the better weekly for that particular week?

[TigerWoodsLibido]

Still good on the EC ensemble

[Deweydog]

3 minutes ago, hawkstwelve said:

I know this is a bit tongue in cheek (what's new!) but given it's relative rock steady prognostications, I don't see it making a giant leap to suddenly look like winter cancel.

So thankfully this isn't something you need to worry about there, Dewey! Step back from the ledge!

Sorry, I just had a moment of weekness.

[Wheezer]

14 minutes ago, Deweydog said:

What happens if next week’s weeklies look better or worse than this week’s weeklies.  Will the weaker week’s weeklies be thrown out in order to defer to the better weekly for that particular week?

That probably is possible but the probability is probably in question.  Maybe.

[TigerWoodsLibido]

Pretty calm with mostly sunny skies and 48F.

[Deweydog]

12 minutes ago, iFred said:

They died happy.

The CFS has been hinting at this for years.

[Gradient Keeper]

12z runs were ugly. GEFS some indication long range that we return to a wetter pattern with mountain snow. All 12z OP/ensembles showed no hope for Cold and SNOW! There is a lot of model noise beyond Day 5. As I've said recently, there are some similarities in my opinion to 2008. Models were atrocious just dreadful until around the 4th and then BOOM! They flipped quickly. Ya gotta believe! C'MON!!!!

00z GFS in 4 hours 51 minutes

00z ECMWF in 7 hours 6 minutes

[TigerWoodsLibido]

[Rubus Leucodermis]

28 minutes ago, hawkstwelve said:

For comparison purposes to a previous post with these numbers, here are the percentage of ECMWF weekly members that show snow for different locations based on the latest run. Some went up, some went a bit down. No huge swings though (outside of KSEA's 18% drop in 6+ inches). These maps don't like KSEA for some reason as evident by PDX having a higher chance of 2 feet of snow than SEA's half foot.

KSEA

6+ inches: 40%

20+ inches: For some reason, this is really low and does not match at all with surrounding locations. Only a couple of members show this as an outcome.

KBLI

6+ inches: 98%

20+ inches: 76%

KPDX

6+ inches: 90%

20+ inches: 46%

The maps for KBLI and KPDX are very pretty, with a surprising number of members showing 3+ feet of snow. I'll leave you with KBLIs just for fun. Roughly 44% (!!!!) show that being an outcome. That's pretty freaking crazy.

And the action starts on the 18th. Shades of 1990. Yes, please!

[Christensen87]

18z a bit better at the end. 

[TigerWoodsLibido]

That's one fun AR matey at the end of the druncle.

[Brian_in_Leavenworth]

2008 shows up again, twice.  And the top analog too.

[Phil]

18z GFS is so close. Strongest PV disruption I’ve seen thus far on guidance.

[TigerWoodsLibido]

Just now, Phil said:

So close. Strongest PV disruption I’ve seen thus far on guidance.

Plenty of time for that to trend better.

[TacomaWaWx]

49/36 today. 

[Phil]

-40C 850mb temps build in N-Canada during week-2. AK/GOA ridge and stretched PV is a good cold loading pattern.

[Meatyorologist]

18z Has a BC slider and a deformation zone over Seattle at the end. Highs in the 20s.

[TigerWoodsLibido]

[TigerWoodsLibido]

Ensemble says good things too

[MossMan]

24 minutes ago, hawkstwelve said:

Inaugural 384hr snowfall map shows Randy getting smacked!

 

That map cannot change for the next 384 hours!!!!! 

[Deweydog]

Just now, MossMan said:

That map cannot change for the next 384 hours!!!!! 

Save it and it won’t!

[Blizzard777]

3 hours ago, MossMan said:

The sky has that pre snowstorm look about it...Only problem is it’s nearly 50 degrees but that’s just a minor detail.  

I thought that same thought earlier today

[TigerWoodsLibido]

Ensemble

Previous run:

[SilverFallsAndrew]

23 minutes ago, TigerWoodsLibido said:

Lot of snow up here. 

[AbbyJr]

1 hour ago, Phil said:

18z GFS is so close. Strongest PV disruption I’ve seen thus far on guidance.

But realistically, what are the odds of it verifying?

[Gradient Keeper]

3 minutes ago, AbbyJr said:

But realistically, what are the odds of it verifying?

2.8%.

[Gradient Keeper]

If only we could somehow painstakingly devise some kind of pill or invent a new, revolutionary vaccine where we all wake up living in Day 12-16 of GFS la-la-land. Wouldn't that be something? Winter weather is a guarantee. The question my friends isn't "Will it snow this Winter?" No. It's "How much snow will fall this Winter?" It'll be cold too. Really cold for part of the Fall and most of the Winter. Temperatures -22 to 30 degrees. In fact, from November 14th to February 20th the temperature never rises to freezing. No more split-flow, messy upper level patterns, inversions, warm atmospheric rivers/pineapples. Nope.

 

Blocking reigns supreme from ~140 to ~160 W always strong, always amplified, and it only pivots with various degrees of tilt. It pivots around like the most enjoyable Merry-Go-Round known in the history of mankind. An endless supply of bitter Siberian goodness floods over us. Failure to not take the vaccine means you will be living in Day 1-11 GFS hell. Nothing but uncertainties, questions, a lack of run-to-run consistency, and worst of all, the unknown.

 

A world where if it snows, it's nearly a miracle. A world of very sad unhappy people, and especially snowmen. It's a world where you are measuring snow in centimeters. No thank you. Is that a world you want to live in? Not me. Seriously. Just take the vaccine. You will awaken to blankets of snow, snow falling, and snowmen standing proudly as far as the eye can see. You won't ever need to 'dream of a White Christmas' ever again. In fact, the Turkey will even be white. C'MON!!!