December Weather In the PNW

[TigerWoodsLibido]

Night shift has been a blast! Clown range shows temps approaching 0F here lol.

[Gradient Keeper]

Animated GIF 850mb Temps Day 1-16

https://imgur.com/kryGPvU

[Gradient Keeper]

Uhhh... 6z GEFS much improved. Better than the Op. Dec 23rd: Troutdale Mean temp down to -9c, Yakima -12c

 

It's still running......

[TigerWoodsLibido]

Uhhh... 6z GEFS much improved. Better than the Op. Dec 23rd: Troutdale Mean temp down to -9c, Yakima -12c

 

It's still running......

Phil is about to look like a savant.

[Gradient Keeper]

Uhhh... 6z GEFS much improved. Better than the Op. Dec 23rd: Troutdale Mean temp down to -9c, Yakima -12c

 

It's still running......

Retrogression begins at Day 8

[Gradient Keeper]

Okay, exhausted going to sleep for a bit. Cya for 12z !

[mountainman]

ok

[van city]

ok

Ok!

[Bryant]

Lining the coast for some strong Fraser outflow then dropping down off the Oregon coast and coming inland south of Eugene. Would be close to a regional event going into an airmass that could produce single-digit temps.

Sweet spot is relative

[van city]

[SilverFallsAndrew]

wrf3km_snow_seattle_60-1.png

 

Incredible. Would be an amazing event for places up north if it even came close to verification!

[Gradient Keeper]

Latest Teleconnection Indices forecast

[Gradient Keeper]

12z GFS

 

Day 1

http://maps1.pivotalweather.com/maps/models/gfs/2017121712/024/500h_anom.na.png

[Gradient Keeper]

Day 2 cut-off low further south than previous runs directly under the block

[Gradient Keeper]

Day 3 block holding stronger, energy/cut-off held to the south of the block

[Gradient Keeper]

Day 3 ridge merger occurring

http://maps1.pivotalweather.com/maps/models/gfs/2017121712/072/500h_anom.na.png

[Gradient Keeper]

Amazing run unfolding

[Gradient Keeper]

Day 4

http://maps1.pivotalweather.com/maps/models/gfs/2017121712/096/500h_anom.na.png

[Gradient Keeper]

Day 5

 

[FroYoBro]

Day 5

 

Here it comes...

[Gradient Keeper]

Model Comparison - Day 5

 

12z Today

and 6z

[Kayla]

Wow, amazing how much the timing has moved up on everything.

[Timmy]

Wow, gfs just caved big time

[Gradient Keeper]

HR 132

[Timmy]

Arctic front sliding south on Christmas eve

[Brian_in_Leavenworth]

Here it comes...

Where did that low come from?  Have not seen that feature before.  Maybe because cold air is coming down over water it develops a low?

[Timmy]

Where did that low come from? Have not seen that feature before. Maybe because cold air is coming down over water it develops a low?

Exactly.

[ShawniganLake]

Wow, GEM is the new gold standard. Every other model is falling inline.

[Gradient Keeper]

Now THIS is fun and worth only getting 3 hours sleep for!

 

Day 6

 

[Timmy]

This mornings gem is even colder

[stuffradio]

Wow, GEM is the new gold standard. Every other model is falling inline.

It has had a couple upgrades this year.

[Timmy]

It has had a couple upgrades this year.

Heard it has a maple syrup dispenser now

[Brian_in_Leavenworth]

It has had a couple upgrades this year.

That is correct, and should be noted.  If it has indeed led the way, I wonder what the correlation scores have been.  Phil would know.  Also to note the NWS does use the Canadian model, as well as the GFS and Euro, but they do not use the UK model, JMA, Navy model, etc, so it must be pretty good.

[Kayla]

Wow. Not very often that you see 480dm and the polar vortex in Central Montana...

[SilverFallsAndrew]

Gem doesn't look colder than the GFS, but keeps it around awhile.

[Gradient Keeper]

Day 8 Block pivoting around, retrogression coming

[SilverFallsAndrew]

Wow. Icebox.

[Timmy]

Wow. Not very often that you see 480dm and the polar vortex in Central Montana...

RIP Kayla, she was alright then she turned into a popsicle

[Gradient Keeper]

Jet being suppressed too

[SilverFallsAndrew]

On second look the GEM is insane, with a reload coming at the end....

 

And ummmm....