December 2016 Observations and Model Discussion for the Pacific Northwest

[VancouverIslandSouth]

And so begins the life of a new weather station: https://www.wunderground.com/personal-weather-station/dashboard?ID=ISAANICH3

 

Turned out to be easier to get going that I thought.

[BLI snowman]

Down to 33 here, on the good side of my expectations.

[snow_wizard]

Down to 34 here now. Actually considerably colder than OLM

[MossMan]

Down to 33 here, on the good side of my expectations.

My truck said 33F when I pulled into our lake house driveway 5pm, nice seeing these cold temps!!

[Gradient Keeper]

00z GFS

Begins in.... 17 minutes

 

Big run tonight. I would love to see the trend continuing of 500mb heights being suppressed just a tad bit longer and 850mb temps a bit colder/spread further south. I would also really like to see the trend of the offshore low Wednesday moving further south. After day 6 we could see things turn even colder. Based on everything I've looked at over the past 3-4 runs/Ensembles here are my thoughts.

 

28% chance models turn colder

41% chance models stick with similar solutions

31% chance models turn less favorable/warmer

 

Feel free to play along (You may need to refresh pages)

Northwest view - http://www.tropicaltidbits.com/analysis/models/?model=gfs&region=nwus&pkg=mslp_pcpn_frzn&runtime=2016112912&fh=0&xpos=0&ypos=197

North America view - http://www.tropicaltidbits.com/analysis/models/?model=gfs&region=namer&pkg=z500_mslp&runtime=2016112912&fh=0&xpos=0&ypos=197

North Pacific view - http://www.tropicaltidbits.com/analysis/models/?model=gfs&region=npac&pkg=z500_mslp&runtime=2016112912&fh=0&xpos=0&ypos=197

Alaska view - http://www.tropicaltidbits.com/analysis/models/?model=gfs&region=ak&pkg=T850&runtime=2016112912&fh=0&xpos=0&ypos=197

[Jesse]

Down to 33 here, on the good side of my expectations.

 

Yeah, 36 here and dropping. Hopefully gradients can stay light with the heaviest precip tomorrow morning.

[Heavy Snow]

 

00z GFS

 

Begins in.... 17 minutes

 

 

 

Big run tonight. I would love to see the trend continuing of 500mb heights being suppressed just a tad bit longer and 850mb temps a bit colder/spread further south. I would also really like to see the trend of the offshore low Wednesday moving further south. After day 6 we could see things turn even colder. Based on everything I've looked at over the past 3-4 runs/Ensembles here are my thoughts.

 

 

 

28% chance models turn colder

 

41% chance models stick with similar solutions

 

31% chance models turn less favorable/warmer

 

 

 

Feel free to play along (You may need to refresh pages)

 

Northwest view - http://www.tropicaltidbits.com/analysis/models/?model=gfs&region=nwus&pkg=mslp_pcpn_frzn&runtime=2016112912&fh=0&xpos=0&ypos=197

 

North America view - http://www.tropicaltidbits.com/analysis/models/?model=gfs&region=namer&pkg=z500_mslp&runtime=2016112912&fh=0&xpos=0&ypos=197

 

North Pacific view - http://www.tropicaltidbits.com/analysis/models/?model=gfs&region=npac&pkg=z500_mslp&runtime=2016112912&fh=0&xpos=0&ypos=197

 

Alaska view - http://www.tropicaltidbits.com/analysis/models/?model=gfs&region=ak&pkg=T850&runtime=2016112912&fh=0&xpos=0&ypos=197

Yup big run tonight. Let's go!

[luminen]

Capilano Lake and the Lions today. Temp was 38F.

[Deweydog]

First dew point freeze at PDX!!!

[Perturbed Member]

36F dp 32F at HIO. Pretty good 

[Heavy Snow]

Capilano Lake and the Lions today. Temp was 38F.

Wow, thats a beautiful view.

[snow_wizard]

First dew point freeze at PDX!!!

Yeee Hawww!!!

[Deweydog]

NAM sure is splitty with overrunner.

[snow_wizard]

I've had about 31" of rain since October 1st, so I probably beat you there

Pretty insane alright. I ended up around 20.

[snow_wizard]

NAM sure is splitty with overrunner.

The NAM should be burned and put out of its misery.

[MossMan]

The NAM should be burned and put out of its misery.

Yeah what a waste of electricity.

[MR.SNOWMIZER]

The clintons invented the nam model. P.O.S.

[TT-SEA]

Quite the beautiful evening out there... snow is sparkling and road is compacted ice and snow that crunches under the tires.   

 

(went for a little drive down the road at half time to take in the wintry scene)

[Deweydog]

The NAM should be burned and put out of its misery.

Careful, it may switch roles and be an emotional lifeline leading up to the next warning shot.

[HighlandExperience]

The clintons invented the nam model. P.O.S.

 

[snow_wizard]

02z HRRR shows precip starting in about 4 hours for greater Puget Sound and continuing, more or less, through 20z Monday.

Does it show everywhere in King County scoring?

[snow_wizard]

Careful, it may switch roles and be an emotional lifeline leading up to the next warning shot.

The thing that drives me nuts is the operational NAM is almost always too cold, and the NAM MM5 over compensates and is usually too warm. Just a mess overall.

[HighlandExperience]

Does it show everywhere in King County scoring?

 

Shows solid precip over King County

[Deweydog]

The thing that drives me nuts is the operational NAM is almost always too cold, and the NAM MM5 over compensates and is usually too warm. Just a mess overall.

It's a horrible model.

 

About the only use is tracking windstorms.

[TT-SEA]

02z HRRR shows precip starting in about 4 hours for greater Puget Sound and continuing, more or less, through 20z Monday.

 

00Z GFS still does not have the precip here by 4 a.m.

 

http://www.tropicaltidbits.com/analysis/models/gfs/2016120500/gfs_mslp_pcpn_frzn_us_2.png

[HighlandExperience]

Looks decent

[snow_wizard]

Looks decent

Holy crap! It shows me in the sweet spot. That would be pretty rare...at least by 21st century standards.

 

This place is odd. It almost always snows at least some when snow in the forecast, but we are rarely one of the big winners.

[stuffradio]

Today locally, we broke the record coldest temp at 500mb for this date. The old record was set in 1948.

[Front Ranger]

Hour 66, the 0z is a little south and 3mb weaker with the approaching low.

[HighlandExperience]

[Deweydog]

Hour 66, the 0z is a little south and 3mb weaker with the approaching low.

We need that third millibar.

[Jesse]

We need that third millibar.

I would think finding a sweet spot for Thursday's system where it is strong enough to give us decent precip but too weak to cause much in the way of warm advection (at least initially) would be optimal.

[Heavy Snow]

The updated run of the 00z NAM shows the over-running event starting sometime around Wednesday 7pm for the Southern Willamette Valley as moisture arrives. It looks like most of the Willamette Valley and parts of SW Washington should be seeing all snow at 10pm. It's still all snow for PDX Metro at Thursday 4am but the changeover to ice or rain looks like it's happening in the Central Valley. 

 

http://www.tropicaltidbits.com/analysis/models/namconus/2016120500/namconus_ref_frzn_nwus_49.png

http://www.tropicaltidbits.com/analysis/models/namconus/2016120500/namconus_ref_frzn_nwus_50.png

http://www.tropicaltidbits.com/analysis/models/namconus/2016120500/namconus_ref_frzn_nwus_52.png

[Front Ranger]

At hour 81, it's 7mb weaker and still further south.

 

Euro definitely led the way with this.

[Front Ranger]

I would think finding a sweet spot for Thursday's system where it is strong enough to give us decent precip but too weak to cause much in the way of warm advection (at least initially) would be optimal.

 

Indeed.

[Deweydog]

I would think finding a sweet spot for Thursday's system where it is strong enough to give us decent precip but too weak to cause much in the way of warm advection (at least initially) would be optimal.

It'd be nice. The current trends are certainly encouraging. Dry or white, por favor.

[snow_wizard]

Today locally, we broke the record coldest temp at 500mb for this date. The old record was set in 1948.

That's a weird record to break. Interesting.

[FroYoBro]

Looks windy. 

[snow_wizard]

At hour 81, it's 7mb weaker and still further south.

 

Euro definitely led the way with this.

I'm rooting for a weaker low also. Less down sloping with a weaker low.

[Jesse]

It'd be nice. The current trends are certainly encouraging. Dry or white, por favor.

Indeed.

 

Any updated thoughts on tomorrow morning? I'm glad to be at 300'.