PNW February 2023 Weather Discussion - Meteorological winter finale

[Doinko]

14 minutes ago, BLI snowman said:

The climate is definitely warmer now, but folks do need to know that there is precedent for subfreezing highs in the lowlands south of Bellingham even as late as mid March before. Just not in the last 100 years.

Fort Vancouver pulled off 5 consecutive highs below freezing from March 12-16, 1867 in what was probably the coldest March since European settlement in the region.

In March 1870, Portland and Seattle both had highs in the 20s on the 13th with a major overrunning snowstorm (6"+) on the 14th.

Seattle had a 32/25 day on March 11, 1897 while Portland was a smidge milder at 35/28 in another crazy cold March for the region. 

And in March 1906, after a fairly mild winter we saw a major regional blast in mid March with a 31/22 day in Portland on the 12th while Seattle was a smidge milder at 34/26. 

Point being that late February is definitely not too late for subfreezing high temps, even though it's obviously a lot more difficult than it was a few weeks (and a century) ago.

 

What do you think about the potential for this event? Seems like more of a gorge component at this stage than 2011

[SouthHillFrosty]

The 6z GEFS was even better 

[T-Town]

2 minutes ago, SouthHillFrosty said:

The 6z GEFS was even better 

The maps without the Tacoma snow hole are more fun and are the ones I choose to believe. 

[SilverFallsAndrew]

3 minutes ago, SouthHillFrosty said:

The 6z GEFS was even better 

There is a lot of potential coming up and not just next week. 

[LowerGarfield]

28F currently with lots of frost.

[snow_wizard]

1 hour ago, SilverFallsAndrew said:

It is pretty amazing this is happening in late February again. 

Indeed.

2011, 2018, 2019, 2022, and then 2021 was mid month.

My coldest max here in 2011 was 33 so I think we could beat that.

[LowerGarfield]

28F currently with lots of frost.

[Cascadia_Wx]

30 minutes ago, BLI snowman said:

The climate is definitely warmer now, but folks do need to know that there is precedent for subfreezing highs in the lowlands south of Bellingham even as late as mid March before. Just not in the last 100 years.

Fort Vancouver pulled off 5 consecutive highs below freezing from March 12-16, 1867 in what was probably the coldest March since European settlement in the region.

In March 1870, Portland and Seattle both had highs in the 20s on the 13th with a major overrunning snowstorm (6"+) on the 14th.

Seattle had a 32/25 day on March 11, 1897 while Portland was a smidge milder at 35/28 in another crazy cold March for the region. 

And in March 1906, after a fairly mild winter we saw a major regional blast in mid March with a 31/22 day in Portland on the 12th while Seattle was a smidge milder at 34/26. 

Point being that late February is definitely not too late for subfreezing high temps, even though it's obviously a lot more difficult than it was a few weeks (and a century) ago.

 

Looking at the post-2/15 period, PDX pulled off a 33/18 day with totally clear skies as recently as 2/26/11. There was Gorge outflow but it wasn’t raging IIRC.

Edited February 16, 2023 by Cascadia_Wx

[snow_wizard]

29 minutes ago, BLI snowman said:

The climate is definitely warmer now, but folks do need to know that there is precedent for subfreezing highs in the lowlands south of Bellingham even as late as mid March before. Just not in the last 100 years.

Fort Vancouver pulled off 5 consecutive highs below freezing from March 12-16, 1867 in what was probably the coldest March since European settlement in the region.

In March 1870, Portland and Seattle both had highs in the 20s on the 13th with a major overrunning snowstorm (6"+) on the 14th.

Seattle had a 32/25 day on March 11, 1897 while Portland was a smidge milder at 35/28 in another crazy cold March for the region. 

And in March 1906, after a fairly mild winter we saw a major regional blast in mid March with a 31/22 day in Portland on the 12th while Seattle was a smidge milder at 34/26. 

Point being that late February is definitely not too late for subfreezing high temps, even though it's obviously a lot more difficult than it was a few weeks (and a century) ago.

 

March 1955 had a high of 29 at SEA.

[The Cats Meow]

Are we in the zone where this is now locked in?

Time for someone to wake the National Weather Service Seattle?

The little blond gal on KOMO or KING 5 last night was pounding the jinx button claiming next week we were going into the freezer.  Hate when I see that.

[SilverFallsAndrew]

1 minute ago, snow_wizard said:

Indeed.

2011, 2018, 2019, 2022, and then 2021 was mid month.

My coldest max here in 2011 was 33 so I think we could beat that.

Here are the late February big dogs up here. 

February 1960 26-29th:

36/19

37/11

42/16

42/12

February 24-28, 1962

37/19

36/15

33/8

36/9

35/28 5" of snow

February 25-28, 1971

37/30 10.5"

34/30 9.5"

34/28 8"

39/11

February 23-27, 2011

32/28 2.5"

30/24 4.5"

28/14  1"

27/10

35/26

 

[Doinko]

1 minute ago, snow_wizard said:

March 1955 had a high of 29 at SEA.

PDX had a low in the teens with that, but no highs below 40. Their coldest high was 29 in March 1960

[snow_wizard]

17 minutes ago, Doinko said:

What do you think about the potential for this event? Seems like more of a gorge component at this stage than 2011

I think you're right.  SEA had a colder max than my location in Feb 2011 which means it was more a northerly blast.  This one will be more NE.  It will be interesting to see how this stacks up with 2011.

[TT-SEA]

10 minutes ago, T-Town said:

The maps without the Tacoma snow hole are more fun and are the ones I choose to believe. 

Its so easy on the GEFS... when the model assumes the Puget Sound and Snoqualmie Pass are basically at the same elevation.  

[BLI snowman]

24 minutes ago, MR.SNOWMIZER said:

The bremerton area had a sub freezing high in march sometime in the last 15 years but i cant remember when it was, i remember the day though. 

2009 and 2019 both pulled off highs in the mid 30s in March in a lot of locales up there. 

'9' years are good!

[Doinko]

2 minutes ago, snow_wizard said:

I think you're right.  SEA had a colder max than my location in Feb 2011 which means it was more a northerly blast.  This one will be more NE.  It will be interesting to see how this stacks up with 2011.

Looking at the Fox12 blog posts from then, looks like we had around 1.5" before and then a bit of east wind, not much though

"Of course one thing models did terrible on was the cloud cover today…almost totally cloudy after 10am.  That kept high temps right around freezing.   In fact it’s kind of cool (meteorologically) that Hood River and The Dalles have had a gusty WEST wind, but temps still below freezing!  That’s because the usual warmer air source (west of the Cascades) is still real chilly.   Basically we’ve got a lot of cold/dry arctic air to moisten up the next 12 hours…but it’ll gradually occur."

[snow_wizard]

5 minutes ago, SilverFallsAndrew said:

Here are the late February big dogs up here. 

February 1960 26-29th:

36/19

37/11

42/16

42/12

February 24-28, 1962

37/19

36/15

33/8

36/9

35/28 5" of snow

February 25-28, 1971

37/30 10.5"

34/30 9.5"

34/28 8"

39/11

February 23-27, 2011

32/28 2.5"

30/24 4.5"

28/14  1"

27/10

35/26

 

I would love a 1971 repeat.  Lots of snow and cold for quite a while.

[snow_wizard]

3 minutes ago, BLI snowman said:

2009 and 2019 both pulled off highs in the mid 30s in March in a lot of locales up there. 

'9' years are good!

That they are.

[Kayla]

This would rewrite the record books for late February cold here. Only event that comes remotely close is 1962 and of course 2019. 1962 is the best match though. Those years never saw consecutive days with highs below zero either. Incredible stuff.

In terms of snowfall this event looks to compare to 2019 best. With that said, another 2-3ft of snow on already a 3ft snow base would be unheard of for here.

[BLI snowman]

21 minutes ago, Doinko said:

What do you think about the potential for this event? Seems like more of a gorge component at this stage than 2011

Yeah, 2011 was more of a top-down trickle in event down here from the NNE while this one seems to have a little more easterly angle to it on its approach. Likely won't be as snowy as 2011 was as a result, but could give it a little extra oomph for the east-wind gap locales.

Kind of looks like a middle ground between the 2011 and 2006 airmasses right now.

[BLI snowman]

14 minutes ago, Cascadia_Wx said:

Looking at the post-2/15 period, PDX pulled off a 33/18 day with totally clear skies as recently as 2/26/11. There was Gorge outflow but it wasn’t raging IIRC.

I think the 26th was a cloudy, overrunning warm front day with flurries for a lot of the region. But they did have a 34 degree high at PDX on the 25th with totally clear skies and pretty light outflow as you said. SEA topped out at 31 that day.

[SilverFallsAndrew]

Looks like the 14 Silver Falls recorded on the 23rd last year was a record for the date, beating out a 16 from 2018. The 19 on the 24th tied the record low from 1962. 

[SilverFallsAndrew]

The ICON does show some snow in the Willamette Valley along the arctic front. It's also a bit further north with the low into CA later in the week, might be something to watch for folks from Eugene south. 

[Cascadia_Wx]

4 minutes ago, BLI snowman said:

I think the 26th was a cloudy, overrunning warm front day with flurries for a lot of the region. But they did have a 34 degree high at PDX on the 25th with totally clear skies and pretty light outflow as you said. SEA topped out at 31 that day.

The 25th is the day I was thinking of then. I can still remember how strange it was to have temps barely above freezing with bright sunshine, relatively high sun angles and light east wind.

[Phil]

2 hours ago, TT-SEA said:

Another fascinating aspect of this pattern is that there is basically no sign of arctic air on Monday morning.   Its not moving in from Alaska or the arctic circle... it forms in place and goes from nothing to near historic cold in a couple days.   

Arctic air doesn’t usually come from Alaska anyways. In this case it’s sitting up over NNE-Canada/Baffin Island as usual, then gets advected straight into SW-Canada, banking up against the terrain.

[Cascadia_Wx]

Meanwhile it’s a frosty 29 degrees here after a low of 27. Got pretty cold again despite the high clouds overnight. High clouds also made for a nice sunrise.

[ShawniganLake]

We aren’t yet at the point in the season where sub freezing highs are exceedingly rare here. We had a 32/26 day here on March 20, 2002.  That seems pretty crazy looking back. Also had a 29F high on the 7th that year, IIRC. 

[Phil]

1 minute ago, ShawniganLake said:

We aren’t yet at the point in the season where sub freezing highs are exceedingly rare here. We had a 32/26 day here on March 20, 2002.  That seems pretty crazy looking back. Also had a 29F high on the 7th that year, IIRC. 

Might not be the best match regionally but there are some interesting large scale overlaps between the 2022/23 and 2001/02 winters.

[Phil]

1 hour ago, SilverFallsAndrew said:

It is pretty amazing this is happening in late February again. 

Considering there’s a major SSW ongoing as we speak, during a Niña/+QBO winter (which are easily the best-performers in the PNW since WWII), is it really that surprising?

I would be more surprised if something *didn’t* happen.

[AlTahoe]

34 minutes ago, snow_wizard said:

Indeed.

2011, 2018, 2019, 2022, and then 2021 was mid month.

My coldest max here in 2011 was 33 so I think we could beat that.

How did you guys do in Late March 2011? I think the final storm for Tahoe was around the 24-29th time frame. I had a -10F the morning after the storm cleared in late March 2011 which was the coldest I have seen in March by a long shot. 

[ShawniganLake]

7 minutes ago, Phil said:

Might not be the best match regionally but there are some interesting large scale overlaps between the 2022/23 and 2001/02 winters.

No big mid winter blasts that year but similar to this year we did have a steady supply of cool weather with accumulating snow every month November through March. 

[TT-SEA]

12Z GFS is much less snowy for western WA going into the cold.    Over the last two days... the focus on the snow going into the cold has been shifting south on the GFS runs.    Previously over Whatcom County and SW BC and now over western OR on the 12Z run.

 

[Phil]

Recent -ENSO/+QBO winters: 2008/09, 2010/11, 2013/14, 2016/17, 2020/21, 2022/23.  Not all blockbusters, but all at least had something.

Interestingly the worst combo in the PNW seems to be +ENSO/+QBO. That list includes the years like 2002/03, 2004/05, 2015/16, etc. Exception is 2018/19, which was “saved” by one of the most significant SSW events ever recorded..though not before Dec/Jan torched massively.

[MR.SNOWMIZER]

Just now, TT-SEA said:

12Z GFS is much less snowy for western WA going into the cold.    Over the last two days... the focus on the snow going into the cold has been shifting south on the GFS runs.    Previously over Whatcom County and SW BC and now over western OR on the 12Z run.

 

Bad trend and it will continue to move south leaving us in a dry blast for much of the area. The area from Eugene to Salem if i had to guess will be the sweet spot. 

[MossMan]

2 minutes ago, TT-SEA said:

12Z GFS is much less snowy for western WA going into the cold.    Over the last two days... the focus on the snow going into the cold has been shifting south on the GFS runs.    Previously over Whatcom County and SW BC and now over western OR on the 12Z run.

 

At least I’m still in the blue!! Not good trends however. 

[Timmy]

This thing is teetering on pretty lame if it doesn’t produce snow at pdx. Canadian isn’t impressive. 
 

Though some decent overnight lows may take place. It may not stand out to anyone but weather nerds

Edited February 16, 2023 by Timmy

[Blizzard777]

Surviving snow north side of house….32* there currently 

70* here in the Smokies but that will change as the north winds happen later this evening.  Should be some fun action with the colliding air masses  

[Kayla]

2 minutes ago, TT-SEA said:

12Z GFS is much less snowy for western WA going into the cold.    Over the last two days... the focus on the snow going into the cold has been shifting south on the GFS runs.    Previously over Whatcom County and SW BC and now over western OR on the 12Z run.

 

This feels like a south WV special to me. Very 2019 esque trajectory. 

[Kolk1604]

2 minutes ago, MossMan said:

At least I’m still in the blue!! Not good trends however. 

Wouldn't really consider it a trend if it comes from a model everyone constantly throws dirt on. 

[AlTahoe]

5 minutes ago, Phil said:

Recent -ENSO/+QBO winters: 2008/09, 2010/11, 2013/14, 2016/17, 2020/21, 2022/23.  Not all blockbusters, but all at least had something.

Interestingly the worst combo in the PNW seems to be +ENSO/+QBO. That list includes the years like 2002/03, 2004/05, 2015/16, etc. Though 2018/19 was “saved” by one of the most significant SSW events ever recorded, but not before Dec/Jan torched massively.

For California this year most closely matches 2010-2011 and then 2016-2017 (mostly for precip not cold)