December 2016 Observations and Model Discussion for the Pacific Northwest

[Phil]

I feel like these long long range models have been all over the place lately.

That's because they have been.

[luvssnow_spokane]

I am exhausted and have basically relegated this event to like so many other we get here. More of a normal mediocre type... I guess that is fine but it is a bit of a bummer. I still believe in miracles and epic though and there is so much winter left!!  Go HAWKS!!   

[bainbridgekid]

NAM is really warm for Monday. 925's above freezing for everyone and onshore flow.

[Heavy Snow]

The last 2 snowstorms I have experienced here at PDX in February 2014 and January 3 2016 all trended colder and snowier right up till the end. In 2014, the models including the GFS kept shoving moisture way south of PDX while KING EURO was the first to give PDX snow like a day away if I remember. For this past January 3 we didnt know PDX would see snow/ice and only a high of 32 until like the night before. This thing is going to come down right to the end, never ever say never. I'm just saying.....

[FroYoBro]

The last 2 snowstorms I have experienced here at PDX in February 2014 and January 3 2016 all trended colder and snowier right up till the end. In 2014, the models including the GFS kept shoving moisture way south of PDX while KING EURO was the first to give PDX snow like a day away if I remember. For this past January 3 we didnt know PDX would see snow/ice and only a high of 32 until like the night before. This thing is going to come down right to the end, never ever say ever. I'm just saying.....

This will definitely be the case for the potential over running system mid week. Events like that are tough to forecast even 24 hours out. We will have to see how much low level cold air we can get in here and what the low is going to be like. Still really have no idea what is going to happen. 

[VancouverIslandSouth]

It's looking more and more like the east coast of Vancouver Island is going to get slammed with this on Monday. I'm hoping Victoria will pick up something as the low departs and the outflow kicks in; would be a long time coming. The overrunning event also looks like it will be a quick but intense hitter. We haven't seen a transition into/out of an outflow like this in years; it does seem to have some parallels with November 2006, but perhaps not quite as cold.

[ShawniganLake]

It's looking more and more like the east coast of Vancouver Island is going to get slammed with this on Monday. I'm hoping Victoria will pick up something as the low departs and the outflow kicks in; would be a long time coming. The overrunning event also looks like it will be a quick but intense hitter. We haven't seen a transition into/out of an outflow like this in years; it does seem to have some parallels with November 2006, but perhaps not quite as cold.

Yea, The 6Z would have laid down close to a foot of snow for places along the east coast of the island.  The 12Z is looking drier, maybe 1/2 of that.  The GEM takes all of the moisture south.  As usual, with these weak lows sliding down the coast and interacting with cold air, we aren't going to know how things are going to work out until we are watching things unfold in real-time.  Model riding every 6 hours is pointless right now. 

[MossMan]

[TT-SEA]

He is f ucking annoying alright. And I thought Tim was bad.

 

 

I have not been saying anything about your forecasts at all (or anyone's forecast really).  You have been pretty reasonable and fair.  

[VancouverIslandSouth]

Yea, The 6Z would have laid down close to a foot of snow for places along the east coast of the island.  The 12Z is looking drier, maybe 1/2 of that.  The GEM takes all of the moisture south.  As usual, with these weak lows sliding down the coast and interacting with cold air, we aren't going to know how things are going to work out until we are watching things unfold in real-time.  Model riding every 6 hours is pointless right now. 

 

Yep, the details won't be ironed out until the eve of the event, but that low has become a consistent feature of all recent model runs. I've never seen a low in that position interacting with incoming Arctic air and not produce at least a few inches of snow along the east coast of the Island. In the past it's always seemed the models were slow to pick up on these surface lows that often form transitioning into Arctic Outbreaks; Feb 2011 was missed until well within a day of it actually happening.

[liquidsnow]

Oh boy, arguments are commencing and I even see some cuss words being exchanged.

 

We're all a little pissed off and angry at the trends but we should direct our anger to those darn warm anomalies, not each other. D**n the models! D**n the Pacific! D**n Global Warming!

[ShawniganLake]

Yep, the details won't be ironed out until the eve of the event, but that low has become a consistent feature of all recent model runs. I've never seen a low in that position interacting with incoming Arctic air and not produce at least a few inches of snow along the east coast of the Island. In the past it's always seemed the models were slow to pick up on these surface lows that often form transitioning into Arctic Outbreaks; Feb 2011 was missed until well within a day of it actually happening.

I definitely agree.  The timing and amount of cold air that makes it thru the Fraser Canyon will be key.  

[MossMan]

Oh that's right, silly me for being optimistic that we see an inch or two after years of jack sh*t. Here: In other news, the models look warmer than ever, the trend is not our friend, and we won't get anything beyond windshield tests. Warning shot my a**. Might as well pull out the #wintercancel now. Where did I put that fork?

 

Better?

Much better! That's the negative Nancy spirit!!

[Phil]

How was 1977/78 out west? That year has been dominating the CPC analogs lately. Not the best seasonal analog by standard application(s), though.

 

http://www.cpc.ncep.noaa.gov/products/predictions/short_range/tools/gifs/500hgt_comp_12gfs814.gif

[Heavy Snow]

This will definitely be the case for the potential over running system mid week. Events like that are tough to forecast even 24 hours out. We will have to see how much low level cold air we can get in here and what the low is going to be like. Still really have no idea what is going to happen.

Yeah if the low level cold air can get entrenched here that will increase our chances for a nice overrunning event. Even that fake cold setup this past January wont be as cold as what we should get.

[HighlandExperience]

12z GFS easily shows the most snow for King County through Tuesday morning out of all recent runs. 00z showed only an inch at best; 12z paints a large portion of King County with 2-3 inches, with the EPSL receiving about 4-6 and the majority of that falling Monday night.

 

Definite potential still.

Yup and WRF still shows a nice coating for most of i-5 corridor. Hope the EURO trends wetter today.

[liquidsnow]

How was 1977/78 out west? That year has been dominating the CPC analogs lately. Not the best seasonal analog by standard application(s), though.

 

http://www.cpc.ncep.noaa.gov/products/predictions/short_range/tools/gifs/500hgt_comp_12gfs814.gif

 

I would take that! There wasn't much "cold" but it was pretty snowy December and January for Southern BC.

[MossMan]

43 degrees, breezy and raining currently.

[westcoastexpat]

How was 1977/78 out west? That year has been dominating the CPC analogs lately. Not the best seasonal analog by standard application(s), though.

 

http://www.cpc.ncep.noaa.gov/products/predictions/short_range/tools/gifs/500hgt_comp_12gfs814.gif

Not great. Warmish and only had two snow events, both were over runners (early January and early February). Pretty much no snow cover that year. That winter was great for everyone east of the Rockies.

[Front Ranger]

12z GFS easily shows the most snow for King County through Tuesday morning out of all recent runs. 00z showed only an inch at best; 12z paints a large portion of King County with 2-3 inches, with the EPSL receiving about 4-6 and the majority of that falling Monday night.

 

Definite potential still.

 

Yeah, 12z ensembles still look promising for some lowland snow Sun evening into Tue morning, and then again with overrunning event.

 

Not super cold, but this a ******* warning shot after all.

[SilverFallsAndrew]

Then there is this....

 

[Kayla]

12z WRF 4km sounding sure looks like a snow profile to me on Monday morning at PDX. Not sure what all the fuss is about.

 

[MossMan]

Yeah I was just about to mention that the WRF shows .5-1 inch overnight Sunday and another inch or two during the day Monday, for most of King/Snohomish/Skagit counties. Even Pierce and Thurston counties get some too.

 

Most widespread WRF lowland snowfall I have seen for a while, even if it is light(er) amounts. I really don't understand the pessimism, but whatever.

 

http://www.atmos.washington.edu/wrfrt/data/2016120212/images_d2/ww_msnow24.84.0000.gif

And still wonderful colors over my house...but I must fight the urge of being positive...

[Heavy Snow]

12z WRF 4km sounding sure looks like a snow profile to me on Monday morning at PDX. Not sure what all the fuss is about.

 

Screen Shot 2016-12-02 at 9.19.06 AM.png

Screen Shot 2016-12-02 at 9.20.38 AM.png

Yeah snow down to the valley floor no question. Soundings are the most accurate snow tool IMHO.

[MossMan]

Yeah if anything, your area has consistently shown to be in a good spot for Monday/Tuesday morning. I would be (semi)excited for the possibilities if I were you. At least an inch or two, most likely more.

I used up all my "likes" last night but I "like" your post! I think the majority of us will see snow, even our southern friends (except the swamp of Puyallup of course)

[BLI snowman]

12z Canadian shows snow on Tuesday morning now down here, rather than Monday. Also looks a bit better and colder with the overrunning storm.

[Timmy]

Wrf gives me close to 8" through Monday. A solid, firm, robust 8"

[HighlandExperience]

I could be wrong, but I think this is the most snowfall the WRF has shown for the Sunday night-Tuesday timeframe for a majority of Western WA. Most of this falls Monday/Tuesday.

 

http://www.atmos.washington.edu/wrfrt/data/2016120212/images_d2/ww_snow72.108.0000.gif

This is definitely the most extensive WRF run for snow. Even the shadowing around Puyallup is now gone. Let's hope the WRF isn't over doing it.

 

The morning run of the EURO will be very telling. If it trends wetter I will feel pretty good about the WRF. The EURO seemed sparse last night.

[SilverFallsAndrew]

Wrf gives me close to 8" through Monday. A solid, firm, robust 8"

 

Personally I am hoping for 9" outside my backdoor. 

[FroYoBro]

Personally I am hoping for 9" outside my backdoor. 

 

I really wouldn't want to watch a weather nerd porno. Ugh. 

[Timmy]

Euro to 48 hrs is noticeably cooler/faster with cold

[Timmy]

Unfortunately looks like the wrf takes away the snow for an overrunning event Thursday.

[Front Ranger]

Euro to 48 hrs is noticeably cooler/faster with cold

 

 

[FroYoBro]

Unfortunately looks like the wrf takes away the snow for an overrunning event Thursday.

 

Like I said, I wouldn't worry about that yet. There is too much that can/will change between now and then. 

[Front Ranger]

At day 3, Euro has slightly stronger/further west shortwave dropping down BC coast.

[Front Ranger]

Also, that rogue low that messes with the offshore ridge is much weaker and further away than on the GFS.

[Kayla]

Nice looking run.

[Front Ranger]

Euro definitely better than GFS at day 5. Lower heights, much weaker low offshore.

[MossMan]

Hope DJ's mom is still doing ok...he is usually awake by the Euro.

[Front Ranger]