PNW November 2021 Wx Obs/Discussion

[snow_wizard]

10 minutes ago, T-Town said:

Foggy and 41 here. 

41?  It dropped to 30 here last night, and is still well below 40.  Wind ruined it for you a few days ago and now fog.

[snow_wizard]

1 hour ago, North_County said:

The current flooding in the Fraser Valley isnt from the Fraser River. It's Nooksack River water that flowed through Sumas and has gotten "stuck" in the Fraser Valley before it can be pumped into the Fraser. Basically, the former Sumas Lake has refilled.

A pretty good article on the history of the drained Sumas Lake and the threat the Nooksack poses to it is here.

https://fvcurrent.com/article/sumas-lake-flooding-history/

I thought for sure the Fraser would have flooded with the craziness that went on in the tributaries.  Interesting.

[snow_wizard]

Looks like another freeze tonight for many places.

[Snownerd3000]

14 minutes ago, hawkstwelve said:

Ensembles, ensembles, ensembles... It's all about the ensembles. 

Lots of noise on the operationals. Much more steady on the ensembles. 

Ensembles...

If I'm not mistaken, it sounds like the word of the day is ensembles 

[MossMan]

On my FB memories this morning…

[snow_wizard]

The 12z GFS actually has another decent mini cold snap just after day 10.  Nice looking surface gradients with that.

[TT-SEA]

Just now, snow_wizard said:

The 12z GFS actually has another decent mini cold snap just after day 10.  Nice looking surface gradients with that.

00Z GFS showed a massive cold trough over the PNW after day 10.... and the 12Z GFS is quite different.   

[snow_wizard]

3 minutes ago, MossMan said:

On my FB memories this morning…

Interesting comment.  The 1880s and 1890s were so snowy they may indeed have begun to consider it passe by then.

That having been said the 1896 event was quite extraordinary for November.  Second only to 1985, and in fact the big snowstorm going into the cold was probably bigger than any single snow in 1985.

[Requiem]

This is cool out in the clown range

[RentonHill]

8 minutes ago, MossMan said:

On my FB memories this morning…

10 inches downtown would be ridiculous. Crazy picture. my old office is on 3rd and marion and its hard to wrap my head around it looking like this. 

[TT-SEA]

12 minutes ago, Requiem said:

This is cool out in the clown range

Its seems like early December is a favored time for cold east wind events.   

[TheNewCulverJosh]

Not sure why anyone would be freaking out.  We appear to be hitting a decent pattern, right around the optimal time (early Dec.).  What's not to like?

[snow_wizard]

The lack of data for the November 1896 event is very frustrating.  We have full records for Seattle and temperature data for Sedro Woolley.  I'm particularly interested in the snowstorm which kicked it all off.  Seattle had over an inch and half of water equivalent and yet only ended up with 6 inches on the ground due to marginal temps when the snow fell.  This really suggests outlying areas could have easily had over a foot on the ground.  It's apparent all of the precip fell as snow even in Seattle because they give the ubiquitous 10 to 1 snow to water ratio as the daily snowfall total.

Once the snow had fallen a significant Arctic blast hit a few days later and brought lows in the teens to the city and Sedro Woolley had three consecutive days with lows below 10 (8,5, and 5).  Might be worth trying to fill in some of the blanks on this one.

[BLI snowman]

Hanging around 34 here still with very thick fog. Will likely be our coldest day of the month with minimal burnoff away from the river.

Inversion season is here!

[snow_wizard]

19 minutes ago, Requiem said:

This is cool out in the clown range

Before that we had nice northerly gradients too.

[T-Town]

40 minutes ago, snow_wizard said:

41?  It dropped to 30 here last night, and is still well below 40.  Wind ruined it for you a few days ago and now fog.

On days like today it doesn’t matter to me if it’s 41 or 31. I do hope the fog burns off and we get to participate in the sunny day. 

[TheNewCulverJosh]

2 minutes ago, T-Town said:

On days like today it doesn’t matter to me if it’s 41 or 31. I do hope the fog burns off and we get to participate in the sunny day. 

Got down to 20 last night and still only 30 here with bright sunshine.  Amazing how just a little E/NE drift can keep temps down here.  Gotta love the high desert.

[snow_wizard]

7 minutes ago, BLI snowman said:

Hanging around 34 here still with very thick fog. Will likely be our coldest day of the month with minimal burnoff away from the river.

Inversion season is here!

Indeed.  Thank God we get inversions here.  They really enhance some of our winter cold, and in some cases make it cold when it shouldn't be.  Last night was quite interesting as mountain locations (not passes) had freezing temps last night even with 850s rising above zero.  The low level cold pool is quite deep.

[snow_wizard]

4 minutes ago, T-Town said:

On days like today it doesn’t matter to me if it’s 41 or 31. I do hope the fog burns off and we get to participate in the sunny day. 

It would drive me crazy having such a hard time getting a freeze.  

[TT-SEA]

1 minute ago, snow_wizard said:

Indeed.  Thank God we get inversions here.  They really enhance some of our winter cold, and in some cases make it cold when it shouldn't be.  Last night was quite interesting as mountain locations (not passes) had freezing temps last night even with 850s rising above zero.  The is low level cold pool is quite deep.

Sunny and 45 here right now... its not that deep.  

[T-Town]

Just now, TheNewCulverJosh said:

Got down to 20 last night and still only 30 here with bright sunshine.  Amazing how just a little E/NE drift can keep temps down here.  Gotta love the high desert.

We spent a few days in Bend in late October a few years ago. Woke up to upper 20s each morning and sat outside at 10 Barrel in the afternoons. I could get used to it.  

[snow_wizard]

One thing to like is almost all model runs shred the PV as we get into early December.

[TT-SEA]

12Z GEFS backs off significantly on the troughing moving inland across the west after day 10... this has been a trend for the last few runs.   

 

 

[SnowWillarrive]

37 minutes ago, MossMan said:

On my FB memories this morning…

Wow is that possible anymore? 

[snow_wizard]

1 minute ago, T-Town said:

We spent a few days in Bend in late October a few years ago. Woke up to upper 20s each morning and sat outside at 10 Barrel in the afternoons. I could get used to it.  

Some of those places can even drop into the upper 20s in August.  I've seen that happen in Liberty some years.

[snow_wizard]

1 minute ago, SnowChild said:

Wow is that possible anymore? 

It certainly is.  1985 was every bit as cold and snowy and much more recent obviously.

[snow_wizard]

5 minutes ago, TT-SEA said:

Sunny and 45 here right now... its not that deep.  

It was during the night.  Probably pretty delicate.  The mesonet has some great mountain locations west of the Cascade crest that give insight into just shallow or deep an inversion is.

[RentonHill]

4 minutes ago, TT-SEA said:

12Z GEFS backs off significantly on the troughing moving inland across the west after day 10... this has been a trend for the last few runs.   

 

 

Starting to look more like the EPS

[snow_wizard]

The GFS and ECMWF still like the Octant 6 / 7 MJO wave emerging in early December.  Something should happen with that.

[snow_wizard]

3 minutes ago, RentonHillTC said:

Starting to look more like the EPS

It still looks like a positive change to me.  Last night's EPS forecast the lowest PNA of any recent runs.

[TT-SEA]

3 minutes ago, RentonHillTC said:

Starting to look more like the EPS

GEFS is definitely backing off.   

Here is the 12Z run yesterday... the 00Z run last night... and the new 12Z run this morning.

 

[T-Town]

13 minutes ago, snow_wizard said:

It would drive me crazy having such a hard time getting a freeze.  

I don’t care about that. I did think I was trading snow for the view when we moved here from Maple Valley but the two big snows we’ve had since then have been good here. So far so good. 

[TacomaWaWx]

Low of 38 here this morning it looks like. 

[SilverFallsAndrew]

The 1896 Event was pretty cold even down this way. SLE had 4-5 sub freezing highs including a 26/12 day. 

[snow_wizard]

I think Tim spoke too soon on the 12z GFS ensemble.  Pretty nice!

[snow_wizard]

24 minutes ago, SilverFallsAndrew said:

The 1896 Event was pretty cold even down this way. SLE had 4-5 sub freezing highs including a 26/12 day. 

That was a great one.

I'll bet you have way better data for that event down there.  Just ridiculous how few stations were operating up here back then, and of the 4 that were operating only two have any useful data that far back.

[TT-SEA]

23 minutes ago, snow_wizard said:

I think Tim spoke too soon on the 12z GFS ensemble.  Pretty nice!

It is definitely backing off before 300 hours... that is more meaningful than what it shows 13-15 days out.    Particularly when we have been in this mode of western troughing being promised in the long range and it never really gets here.   That is just the reality of the situation right now.    Go back 2 weeks... we were talking about deep troughing for right now.  I am not saying it will stay this way all winter... but things need to move up in time and that is not happening yet.

Unfortunately... this also means a generally wet pattern will likely continue. 

[Cascadia_Wx]

Low of 31 and frosty here, up to 35 now that fog has formed.

[RentonHill]

19 minutes ago, TT-SEA said:

It is definitely backing off before 300 hours... that is more meaningful than what it shows 13-15 days out.    Particularly when we have been in this mode of western troughing being promised in the long range and it never really gets here.   That is just the reality of the situation right now.    Go back 2 weeks... we were talking about deep troughing for right now.  I am not saying it will stay this way all winter... but things need to move up in time and that is not happening yet.

Unfortunately... this also means a generally wet pattern will likely continue. 

Here’s what I posted on the 10th

[Gradient Keeper]

2 hours ago, hawkstwelve said:

Ensembles, ensembles, ensembles... It's all about the ensembles. 

Lots of noise on the operationals. Much more steady on the ensembles. 

Ensembles...

Exactly. The Op runs are all over the place after Day 7 which certainly isn't new nor a surprise. The ensembles however have been very consistent and insistent that the Pacific shuts down with a ridge in the vicinity of ~165-160 W which is a bit too far west for the goodies.

00z ECMWF in 10 hours 44 minutes