November 2017 PNW Discussion Thread

[Jesse]

Haven’t been tracking things the last couple days. The upcoming trough sure has been watered down.

[SilverFallsAndrew]

Haven’t been tracking things the last couple days. The upcoming trough sure has been watered down.

 

[Jesse]

Artic blast!

[BLI snowman]

Haven’t been tracking things the last couple days. The upcoming trough sure has been watered down.

 

Not really. And our temps look like they will be more impressive here thanks to the surface lows.

[ShawniganLake]

850mb is shown to bottom out at -8C here. 925mb at -4C. That’s pretty impressive for Nov 3.

 

The speeding up of tomorrow’s system is definitely hurting our snow chances to the north. Heaviest precip falls during the middle of the day.

 

12Z CMC is further north with the precip on Sunday when compared to the GFS.

[Deweydog]

Haven’t been tracking things the last couple days. The upcoming trough sure has been watered down.

Seems pretty consistent.

[SilverFallsAndrew]

Seems pretty consistent.

 

I agree. I think his post was more of a conversation starter...

[Jesse]

Not really. And our temps look like they will be more impressive here thanks to the surface lows.

Maybe I’m just comparing it to the crazier runs several days ago. Been preoccupied with school and Halloween activities since.

[Kayla]

Maybe I’m just comparing it to the crazier runs several days ago. Been preoccupied with school and Halloween activities since.

 

Lowland snow is more likely in some areas than ever before. Post Halloween blues??

[Jesse]

Lowland snow is more likely in some areas than ever before. Post Halloween blues??

Blues? No had an awesome Halloween. Just was making a comment my perception of the models.

 

I don’t think there will be any lowland snow down here though. Maybe up north.

[Kayla]

Blues? No had an awesome Halloween. Just was making a comment my perception of the models.

 

I don’t think there will be any lowland snow down here though. Maybe up north.

 

Just giving you a hard time.  Glad to hear you had a great Halloween! 

 

And I agree, looking better up north.

[Deweydog]

Maybe I’m just comparing it to the crazier runs several days ago. Been preoccupied with school and Halloween activities since.

I think the coldest few runs had us getting into the mid 520's thickness-wise. Not too far off from what's currently shown.

[TT-SEA]

12Z ECMWF is much farther north with the Saturday night and Sunday system.   

 

It now shows southerly flow around Portland on Sunday.    And what appears to be a 43-degree drizzle fest around Seattle.  

[High Desert Mat!]

How much am I gonna get!?!?!? Lol

[SilverFallsAndrew]

Can I just reiterate what a joke the WRF low resolution snow maps are. Really no point in looking at them other than for shits and giggles.

[TigerWoodsLibido]

I think the EC will verify.  It's too early for snow yet.

[TigerWoodsLibido]

Can I just reiterate what a joke the WRF low resolution snow maps are. Really no point in looking at them other than for shits and giggles.

 

Seriously...it has almost an inch in Monmouth.  Zero chance that happens.

[SilverFallsAndrew]

I would be happy with some flakes in the air over the weekend and a nice hard freeze Sunday or Monday night.

[TT-SEA]

Can I just reiterate what a joke the WRF low resolution snow maps are. Really no point in looking at them other than for shits and giggles.

 

Saw some massive errors with the WRF last winter!  

[BLI snowman]

Can I just reiterate what a joke the WRF low resolution snow maps are. Really no point in looking at them other than for shits and giggles.

 

I would have easily had over 40" last winter had they verified.

[ShawniganLake]

Saw some massive errors with the WRF last winter!

It seems to do better up here when it’s an overrunning situation with the cold air already in place.

[ShawniganLake]

12z ECMWF shows more snow in the Puget Sound area by Sunday evening than both the 12z yesterday and the 00z last night, although it's still only a trace or so most areas (except Whatcom).

 

I'm wondering if the model snowfall maps account for wet-bulb/dew points? Based off the surface temps shown at the time (upper 30s) and the 850s (-5c) I would think it wouldn't show any snow.

 

http://wx.graphics/models/ecmwf/2017110112/washington/ecmwf_acc_snow_washington_108.png

Interesting. Looks decent for the Fraser outflow areas.

[Jesse]

12Z ECMWF is much farther north with the Saturday night and Sunday system.

 

It now shows southerly flow around Portland on Sunday. And what appears to be a 43-degree drizzle fest around Seattle.

Glad to hear things aren’t trending warmer.

[MR.SNOWMIZER]

That would be the most snow i have ever seen at hood canal this time of year if it's correct. 

[luvssnow_spokane]

12Z ECMWF is much farther north with the Saturday night and Sunday system.   

 

It now shows southerly flow around Portland on Sunday.    And what appears to be a 43-degree drizzle fest around Seattle.  

Looks the the ECMWF wobble is kicking in. I would not be surprised to see this shift a bit southward on future runs.

[Jesse]

That would be the most snow i have ever seen at hood canal this time of year if it's correct. 

 

We were hiking around the Lake Cushman area in early September this year and I was thinking about how frequently that area gets buried. This could be one of those times.

[Geos]

12z GFS shows varying amounts of snow from Everett to Olympia and up in Whatcom. Still not buying it for the greater Puget Sound I-5 corridor.

 

 

Starting to think will see some flakes falling at like 34-35 deg. down to 500 ft.

[Geos]

Interesting. Looks decent for the Fraser outflow areas.

 

Showing an inch here. Interesting.

 

Snow in the wording for Saturday night here now.

[Phil]

For giggles, the 12z EPS control run has 850s close to -30C near the US/Canada border on November 11th. As far as I'm aware, that has never occurred in the satellite era, to this point.

 

Edit: And near -30C in Alberta by days 6/7.

[TigerWoodsLibido]

I feel like models are really struggling with this because it's so unusual to have this setup like this so early.  Who knows what the temp variances will be.  IIRC, the late Nov, 2003 snow event in Eugene was expected to have snow levels down to 1500-2000 feet and it ended up with heavy enough precip to bring the snow level to the surface.

[Jesse]

For giggles, the 12z EPS control run has 850s close to -30C near the US/Canada border on November 11th. As far as I'm aware, that has never occurred in the satellite era, to this point.

 

Haven't heard much from you lately. What are your thoughts right now going forward? Seems like November won't be as much of a western torch as you were anticipating, at least for the next 7-10 days.

[MR.SNOWMIZER]

We were hiking around the Lake Cushman area in early September this year and I was thinking about how frequently that area gets buried. This could be one of those times.

I had a place up there for about 2 years and I always knew they received a ton of snow but I was blown away how much I seen up there. I remember posting pics but it snowed 30 inches in like 20 hrs once. Had 37 on the ground and snow was on the ground for 3 months.

[Phil]

Haven't heard much from you lately. What are your thoughts right now going forward? Seems like November won't be as much of a western torch as you were anticipating, at least for the next 7-10 days.

Yeah, sorry I've been swamped with work lately.

 

Definitely not a good short term forecast on my part. Much faster MJO/KW propagation than I was thinking, so that early November ridge and mid-November trough were pushed forward quite a bit compared to my initial idea, even though the discontinuous retrogression and NPAC amplification verified.

 

Since the MJO/KW is also shallower (given the propagatory speed is a direct consequence of depth), it will orbit back into the IO/EHEM much more quickly, as well, which statistically favors the coldest air being centered over North America as heat/mass fluxes increase into Eurasia. So, much of North America will likely experience colder than average temperatures for the month of November, given the PV will be on our side of the pole for the aforementioned reasons.

 

So, November likely finishes below normal almost everywhere except for the E/SE USA and Alaska, if I had to guess right now.

[Jesse]

Yeah, sorry I've been swamped with work lately.

 

Definitely not a good short term forecast on my part. Much faster MJO/KW propagation than I was thinking, so that early November ridge and mid-November trough were pushed forward quite a bit compared to my initial idea, even though the discontinuous retrogression and NPAC amplification verified.

 

Since the MJO/KW is also shallower (given the propagatory speed is a direct consequence of depth), it will orbit back into the IO/EHEM much more quickly, as well, which statistically favors the coldest air being centered over North America as heat/mass fluxes increase into Eurasia. So, much of North America will likely experience colder than average temperatures for the month of November, given the PV will be on our side of the pole for the aforementioned reasons.

 

So, November likely finishes below normal almost everywhere except for the E/SE USA and Alaska, if I had to guess right now.

 

No worries. Thanks for the update. 

 

I am curious how this will affect things going forward, since most conventional wisdom around here seemed to point to a warm November.

[MR.SNOWMIZER]

Just even having a chance of some snow in the forecast this early for some places west of the cascades is pretty remarkable.

[seattleweatherguy]

Komo says snow level as low as 500 ft I'm awfully close to that elevation

[ShawniganLake]

18z Nam looks a little further north with things on the weekend too.

[TigerWoodsLibido]

Really hope this northern trend doesn't continue with these systems. Would put us in the warm sector more often.

[Jesse]

Really hope this northern trend doesn't continue with these systems. Would put us in the warm sector more often.

 

The track of this storm will set the tone for the entire winter. Better hope it works out.

[High Desert Mat!]

For giggles, the 12z EPS control run has 850s close to -30C near the US/Canada border on November 11th. As far as I'm aware, that has never occurred in the satellite era, to this point.

 

Edit: And near -30C in Alberta by days 6/7.

Maps?