PNW February 2023 Weather Discussion - Meteorological winter finale

[RCola]

Looks like EPS is slightly colder but slightly less snow. Overall though the consistency has been rock solid for several runs now. We'll see what happens in the last 30 hours of the run.

[Deweydog]

Forecast contest????

This one might be too easy though…

[RCola]

Final mean snowfall for the EPS.

Overall, in comparison to the 12z run, we have a little less snow in the mountains for BC, WA, and OR, a little less snow in the BC lower mainland, very little change along the Puget Sound (perhaps a slight decrease), and a slight increase for the Willamette Valley. 

[snow_wizard]

22 minutes ago, Deweydog said:

Forecast contest????

This one might be too easy though…

I think SEA and PDX both have a shot at sub 30 highs.  Just that would be historic.  Obviously snowfall could have a big impact on just how cold it gets.

[Deweydog]

1 minute ago, snow_wizard said:

I think SEA and PDX both have a shot at sub 30 highs.  Just that would be historic.  Obviously snowfall could have a big impact on just how cold it gets.

In order for that to happen you’d pretty much have to have stratiform precip with decent low level dry advection. PDX could maybe pull it off with screaming dry advection out of the gorge but it’d be quite the stretch. 2/17/06 managed a 32 degree daytime high with the outflow, but at this point a week’s worth of higher sun angles means something. 

[Christensen87]

06z is still golden, the trends continue…

[TT-SEA]

The EPS is showing a sub-freezing highs at SEA and PDX... that is seriously impressive.   

[TT-SEA]

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.   

[umadbro]

I haven’t told anyone a thing except for my dad who follows the models. We’ve both just grunted at each other and moved along to sports.

[Jbolin]

2 minutes ago, umadbro said:

I haven’t told anyone a thing except for my dad who follows the models. We’ve both just grunted at each other and moved along to sports.

As real men do.

Nice job  

[T-Town]

28 minutes 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.   

How is it possible for air to form in place?

[TT-SEA]

The 06Z EPS and control run go out through 144 hours (Tuesday evening) and both were a little faster than their 00Z runs.  It will be interesting to see how the timing works out in terms of the balance between cold air and moisture.    Faster timing would likely mean less snow in the Seattle area... and the 06Z EPS and control run don't show much snow up here on Tuesday.   Very different than the 00Z ECMWF which was slower and kept the moisture plume over western WA as cold air slowly trickled in. 

 

[TT-SEA]

5 minutes ago, T-Town said:

How is it possible for air to form in place?

Well the purple colors just blossom in place... no idea how that works!   The 850mb map for next Monday morning does not look like anything even remotely close to interesting and yet by Wednesday and Thursday we will have arctic air and that is pretty much a given at this point.   

[SilverFallsAndrew]

18 minutes ago, TT-SEA said:

Well the purple colors just blossom in place... no idea how that works!   The 850mb map for next Monday morning does not look like anything even remotely close to interesting and yet by Wednesday and Thursday we will have arctic air and that is pretty much a given at this point.   

It’s kind of funny you can’t figure this out. Lol

Edited February 16, 2023 by SilverFallsAndrew

[TT-SEA]

Just now, SilverFallsAndrew said:

It’s kind of funny you can’t figure this out. Lol

Obviously the same cold air would not appear as anomalous in northern Canada... but usually we see a stronger signal to north just a couple days before it arrives here.    If I just look at that 850mb for Monday morning it seems like there is nothing imminent.    But it sure becomes imminent quickly!  

[SilverFallsAndrew]

1 minute ago, TT-SEA said:

Obviously the same cold air would not appear as anomalous in northern Canada... but usually we see a stronger signal to north just a couple days before it arrives here.    If I just look at that 850mb for Monday morning it seems like there is nothing imminent.    But it sure becomes imminent quickly!  

I know what you are saying, but you can still tell where the cold comes from. 

[SilverFallsAndrew]

At this point this feels bigger than what we saw last February. I wouldn’t say lowland snow chances are dropping, but it does seem like lower chances for significant widespread lowland snow. As is often the case with arctic air. 06z took the 510 line to PDX. 

[TT-SEA]

1 minute ago, SilverFallsAndrew said:

I know what you are saying, but you can still tell where the cold comes from. 

Yes... of course it comes from somewhere.    Its just an amazingly fast developing situation.    One might say explosive!  

[SilverFallsAndrew]

5 minutes ago, TT-SEA said:

Yes... of course it comes from somewhere.    Its just an amazingly fast developing situation.    One might say explosive!  

Makes me put more faith in it than I usually would. It’s very aggressive in how it develops and advects into our region. Not something that sags south at 2mph and gets hung up in customs. 

Edited February 16, 2023 by SilverFallsAndrew

[TT-SEA]

Just now, SilverFallsAndrew said:

Makes me put more faith in it than I usually would. It’s very aggressive in how it develops and advects into our region. Not something that sags south at 2mph and gets hung up in customs. 

Totally agree.    

[SilverFallsAndrew]

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

[Doinko]

1 hour ago, TT-SEA said:

The EPS is showing a sub-freezing highs at SEA and PDX... that is seriously impressive.   

Could you post this chart for the OP?

[SilverFallsAndrew]

SLE is already running 0.8F colder than January. 

[Jakewestsalem]

Wonder if Jim Cantore is booking flights yet?

Anybody know where we are alphabetically with naming winter storms?

[TT-SEA]

4 minutes ago, Doinko said:

Could you post this chart for the OP?

I mean... this is just silly considering its the ECMWF.   

 

[SilverFallsAndrew]

Just now, TT-SEA said:

I mean... this is just silly considering its the ECMWF.   

 

Some historical precedent for something like this as late as Valentine’s Day, but for late February you would have to go back into Jim’s archives to find something even close. 

[MR.SNOWMIZER]

the 06z gfs is weaker with that low Tuesday but after that it is once snow chance after another for the entire area through the entire run. Reminds me of feb 2019 here.

[Meatyorologist]

That 2010-11 analog is looking better again.

[Timmy]

[Doinko]

On 1/31/2023 at 5:37 PM, Meatyorologist said:

Late February is kind of goated, a relatively untapped time of year. The airmasses are still quite decent but a lot needs to go right to stay below freezing all day given the higher sun angles. 1956, 1990, and 2011 are the best examples (even 2022 was pretty cold despite being so dry.

What I'm saying is that it's climatologically feasible for a 26/15 type day if all were to go right, albeit quite defficult. But if it were to happen, records would be shattered.

I remembered this post, seems relevant now

[TT-SEA]

1 minute ago, Eujunga said:

I've said this before about anomaly maps: they can be deceiving. If you look at an absolute 850mb temperature map, you can see the movement of the cold air more clearly. It doesn't appear to "just blossom in place."

Definitely can be deceiving.   Either way... this event looks much more explosive than our usual slow bleed situations.  

[Rubus Leucodermis]

25 minutes ago, Jakewestsalem said:

Wonder if Jim Cantore is booking flights yet?

Anybody know where we are alphabetically with naming winter storms?

Sorry, if you live west of the Mississippi, you don’t really count. There will be no name for this storm unless the East is affected.

[BLI snowman]

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.

 

[MossMan]

Currently cloudy and 33 degrees. 

[TacomaWx]

4 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.

 

Yeah 2011 wasn’t even that long ago. 2018 had sub freezing highs in some locations too. It could definitely happen next week. 

[TacomaWx]

Low of 32 this morning for the 29th freeze of the season. We could get pretty close to the amount of freezes we had in winters like 08-09, 16-17 and 18-19. Those winters had about 40-45 freezes which is a lot for my location. 

[Jbolin]

Party Time, let's do this sh*t.

[MR.SNOWMIZER]

9 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.

 

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. 

[LowerGarfield]

8 hours ago, SouthHillFrosty said:

Still different than the GFS…. But closer 

The euro is incredible for my location. Please let's make it happen.

[SnowWillarrive]

I want my February 1916