December 2023 Weather in the PNW

[SnowWillarrive]

22 minutes ago, Slushy Inch said:

Should be worth getting out the skis at least. Surprised by quality of this run, though it is warmer in B.C.  Alaska ridge underwhelming.

500 foot snow levels sound nice.

[MossMan]

19 minutes ago, Slushy Inch said:

Could pull of a miracle slushy inch with cool onshore flow. Maybe a pscz.

 

[SilverFallsAndrew]

1 hour ago, Cascadia_Wx said:

How is the Kristmas Ketamine Klinic out there treatin ya?

All my heroes are at the methadone clinic!

[MR.SNOWMIZER]

Merry Christmas people!

Btw this is the wettest Nov Dec on record here since 2004.

I've received 36 inches of rain since Nov 1. 

15.6 for the month so far. 

LOL

 

[MossMan]

3 minutes ago, MR.SNOWMIZER said:

Merry Christmas people!

Btw this is the wettest Nov Dec on record here since 2004.

I've received 36 inches of rain since Nov 1. 

15.6 for the month so far. 

LOL

 

I only have 4” more than that total…For the year!

[Rubus Leucodermis]

I have to confess disappointment. I was hoping for a sea of 60-burgers, yet this is the best torching I can see.

What sort of cheap sh*t El Niño is this? I want my money back!

 

[Cold Snap]

Merry Christmas everyone! Hopefully we can get this SSW to work out for us and finally break that January curse!

[MossMan]

6 minutes ago, Cold Snap said:

Merry Christmas everyone! Hopefully we can get this SSW to work out for us and finally break that January curse!

February into March 2019 redux except it will be a January into February extravaganza this time! 

[MR.SNOWMIZER]

40 minutes ago, MossMan said:

I only have 4” more than that total…For the year!

86 for the year

[Cascadia_Wx]

Sort of a chilly and raw Christmas out there. Breezy east winds and rain at times much of the day. 42/38 spread here so far.

Picked up a little over 1/3” of rain today, which pushes me to nearly 9” for the month to date.

[MR.SNOWMIZER]

I'm on the sw slope of gold mountain and green, pretty sure I get upslope enhanced rain here because of those mountains .

The mountains are only 1700ft but they create weather.

 

 

 

[MossMan]

6 minutes ago, MR.SNOWMIZER said:

86 for the year

I typically average 60” for the year but I’m only around 40” this year unfortunately. 

[RayRay]

Hills are bare here in Methow Valley… snow has been slow all day. Went from 4 inches to 1.5 expected in the forecast…. Rip the snow…

[Gradient Keeper]

It is now the warmest it has been all day at 39.2. I had been hovering between 36.1 and 36.5 all day. A gusty to at times raging east wind continues.

00z GFS in 1 hour 24 minutes

[Ken in Wood Village]

1 minute ago, Gradient Keeper said:

It is now the warmest it has been all day at 39.2. I had been hovering between 36.1 and 36.5 all day. A gusty to at times raging east wind continues.

00z GFS in 1 hour 24 minutes

Yea, I've only reached 38.5° today. Never reached 40° 

[MossMan]

Yum

[AlTahoe]

4 hours ago, Cascadia_Wx said:

When was the last time a non-historic weather event happened in the Tahoe basin? Seems like it’s been an historically long time.

It's either an all time record for least snowy or most snowy since 2016. No such thing as normal anymore. Had 3rd most snowy Jan 2017, Snowiest Feb 2019, snowiest Dec 2021, Coldest March ever 2023.

Least snowiest Oct - Dec 2018. 2020. and now 2023 

Also after the snowiest Dec ever recorded 2021 we had the least snowiest Jan - March ever recorded 2022

[the_convergence_zone]

Up to 0.60 today, 9.14 on the month.

[Phil]

3 hours ago, Meatyorologist said:

Don't know about that one... Despite KSEA's climate warming by ~1.5F, our average annual snowfall has increased by a few tenths of an inch from the 1981-2010 normals.

I think the logic behind what you're saying is that since most of our snowfall occurs between 32-35F, marginal increases in temperature will boost snow levels in the region (that are often already tenuously balanced around sea level) by hundreds of feet, leaving millions with rain or unproductive wintry precipitation.

I've heard that argument used often, and it always sounds wrong... Our region's common snowfall type feels less like an incedental occurence of happenstance, and more related to a fundamental property of our natural typology.

When snowing without direct Arctic influence, temperatures seem 'magnetized' to ~32-33F, instead of 'luckily settling around 32-33'. There are two general scenarios in which we recieve marginal snowfall; also comprising of 90% of our region's lowland snow budget; them being overruning warm fronts, and postfrontal convective environments. My running guess is that these snowfall methods settle just above freezing due to latent heat absorbtion as falling precipitation melts. Without the aid of continential cold/dry air, there's little to influence the sfc environment to cool past 32F, but with latent heat absorbtion, there is an incredible amount of cooling happening inside the melting layer.

Warming the Earth will probably marginally increase the amount of time it takes for latent heat to cool us down to the freezing level in those situations, as well as slightly reduce the frequency and duration of these events, since we'd be starting from a slightly higher T/Td overall in every situation. But since the melting layer in our current climate already extends well past the Earth's surface, we probably only stand to lose 5-10% on both fronts, and endure a meaningless loss in annual snowfall. (Though I will admit, concrete-related UHI is doing a lot of damage to marginal snow prospects within the metro area.)

As for where our annual snowfall averages are headed in the long term? Well right now it's pretty evident that stochastic Arctic snowstorms have more leverage on our annual snowfall than the steady slight downward trend in marginal events. Yeah, it sucks to miss out on a collective 8" of marginal snowfall over the course of a decade. But when you make all that up in six hours during an Arctic overrunning event, and then do the same thing a week later for no good reason, then do that same thing again for three of the next four winters, it doesn't really matter all that much..

PNW snowfall averages (and overall winter severity) has declined more than anywhere else in the country in the post-WWII era.

Don’t get hoodwinked by recency bias.  Intradecadal variability can mask multidecadal trends temporarily but at some point you get the other end of the stick.

[Slushy Inch]

2 minutes ago, Phil said:

PNW snowfall averages (and overall winter severity) has declined more than anywhere else in the country in the post-WWII era.

Don’t get hoodwinked by recency bias.  Intradecadal variability can mask multidecadal trends temporarily but at some point you get the other end of the stick.

I’m going to pretend that map doesn’t exist. 

[Phil]

Just now, Slushy Inch said:

I’m going to pretend that map doesn’t exist. 

Unfortunately the west coast gets the short end of the stick w/rt the broadening Hadley Cell descending branch.

[the_convergence_zone]

5 hours ago, Phil said:

Hmm.

https://x.com/ryanmaue/status/1739182864405598498?s=46&t=656Z973wLtGKaIyhhq_7QQ

I gave this a quick read, it seems like the argument is that SO2 from a high latitude volcano can cause one season of extreme cooling in a single hemisphere. The decadal global cooling events were mostly caused by the tropical volcanoes as expected. There just happened to be some cold decades with multiple eruptions within a few years that have muddled the records a bit. 

I’ve seen a similar thesis before — some have argued that the global warming “hiatus” in the late 2000s-early 2010s was also volcanic induced by a number of small eruptions that occurred around that time. 

Largely this paper was about trying to get the different proxy records to agree and clearly there is still a ton of debate there over which volcanoes erupted in which year and the cause and effect relationships are largely circumstantial. 

Still lots to learn about aerosol feedbacks for sure…

[Phil]

9 minutes ago, Phil said:

PNW snowfall averages (and overall winter severity) has declined more than anywhere else in the country in the post-WWII era.

Don’t get hoodwinked by recency bias.  Intradecadal variability can mask multidecadal trends temporarily but at some point you get the other end of the stick.

Expressed as a value (instead of percent) it stands out even more. Also positive correlation to changes in winter duration.

The decrease in EPSL is over 400pts, which is a loss of 75% in some places (where total AWSSI is now 100-200pts total).

[Rubus Leucodermis]

45 minutes ago, Ken in Wood Village said:

Yea, I've only reached 38.5° today. Never reached 40° 

Min of 42˚F, max of 48 here (currently 48). Looks like you’re really getting affected by gorge outflow.

[Rubus Leucodermis]

0.37" since midnight, 10.71" for the month.

[Frontal Snowsquall]

From our family to yours, I want to wish you all a Merry Christmas!  

My to all of you will be a PNW Arctic Blast and regional snowstorm in about a month from now.  

[SnowWillarrive]

54 minutes ago, Phil said:

Unfortunately the west coast gets the short end of the stick w/rt the broadening Hadley Cell descending branch.

Going forward Hadley Cells expanding will significantly reduce snow along the I-95 corridor. Bank on it. Southern Europe is already being impacted. The lack of snow south of Boston should be telling.
 

You are at a much more southerly latitude. Of course things can change and perhaps there are climate surprises in store. 

[ShawniganLake]

3 hours ago, MR.SNOWMIZER said:

Merry Christmas people!

Btw this is the wettest Nov Dec on record here since 2004.

I've received 36 inches of rain since Nov 1. 

15.6 for the month so far. 

LOL

 

Seems like a very localized thing.  Don’t think many areas are close to a record wet Nov Dec. 

[ShawniganLake]

Power is on here but about 10000 customers are without power across the south coast of BC tonight 

[Phil]

23 minutes ago, SnowWillarrive said:

Going forward Hadley Cells expanding will significantly reduce snow along the I-95 corridor. Bank on it. Southern Europe is already being impacted. The lack of snow south of Boston should be telling.
 

You are at a much more southerly latitude. Of course things can change and perhaps there are climate surprises in store. 

Depends where along in the I-95 corridor. Average snowfall has actually increased in Philly/NYC/Boston in the post WWII era.

Down here it has decreased, but not nearly to the extent it has in the lowland PNW (and west of the BR it has actually increased). We’re less reliant on temperatures than you so the magnitude of the decline is less (and overall warming has been less out here, though that’s probably due to increased moisture/latent heating as dewpoints have been skyrocketing especially in summer).

[Requiem]

Could be some advisory level easterly winds Wednesday into Thursday for the metro as low pressure approaches the area. Tentatively a bit of a downslope aspect to it as well...

[MWG]

High of 46F and currently 43F. We have a wind advisory from Tuesday night til Wednesday. 

[Dave]

Drove over the pass to Bend this afternoon. It rained the entire way. Even at the pass level it was negative on the splat test. Pretty disappointing. There is about 6 inches of snow at the pass. Blech.

[Dave]

Ray Benson sno park.

 

[SilverFallsAndrew]

5 minutes ago, Dave said:

Ray Benson sno park.

 

I was thinking of going to Daly Lake tomorrow. 

[Phil]

00z GFS delays W1 to W2 transition in SSW.

[Dave]

4 minutes ago, SilverFallsAndrew said:

I was thinking of going to Daly Lake tomorrow. 

Not the time of year I would normally suggest going there, but it should at least be accessible. The snow line was at about 3 thousand feet, but had only a couple of inches other than where it was plowed.

[SilverFallsAndrew]

2 minutes ago, Dave said:

Not the time of year I would normally suggest going there, but it should at least be accessible. The snow line was at about 3 thousand feet, but had only a couple of inches other than where it was plowed.

Yeah, if anyone has been up there it should be pretty smooth sailing. 

[Phil]

6 hours ago, TigerWoodsLibido said:

Beautiful Christmas 2023. Truly memorable 54F with moderate rain. Good to see the weeds and overwintering hornets doing well 

You have the same candy cane lights as us.  

[SilverFallsAndrew]

The pattern the next 10 days is just complete crap. Worst of the worst.