Part I - January 2020 Weather Discussion for the PNW

[Meatyorologist]

Big, unconsolidated eddies are really stupid anyways. Let's get a Euro-type situation where a closed-off low slams into the coast. Better thermodynamic control and moisture transport.

[Gradient Keeper]

I believe the line Rob is,

 

You serious Clark?

Haha, indeed it is.

[Cloud]

It's about to bring that snowmaker low a little bit north this run at hour 192. May very well be snowy all around. 

 

Nope, not this run. Bouncing all over the place then goes to Cali. Mostly dry. 

[Skagit Weather]

850 mb temps of -20C stretching from YVR to PDX? When was the last time 850 mb temps dropped below -20C in Seattle?

 

[Gradient Keeper]

PDX High/Low temps
Monday: 34(at 1 PM) / 26
Tuesday: 12 / 7
Wednesday: 10 / 1
Thursday: 8 / 4
Friday: 16 / 8

[Gradient Keeper]

Minimum 850mb Temps
Seattle: -19c
Bellingham: -19c
Portland: -19c
Salem: -18c
Eugene: -16c
The Dalles: -27c
Pendleton: -29c
Moses Lake: -26c
Spokane: -26c

[Jbolin]

PDX High/Low temps

Monday: 34(at 1 PM) / 26

Tuesday: 12 / 7

Wednesday: 10 / 1

Thursday: 8 / 4

Friday: 16 / 8

These numbers are just plain stupid, esp for this area.

[Gradient Keeper]

6z GEFS trended colder.
PDX mean temp down to -13c
Seattle -15c
Yakima -18c

[Gradient Keeper]

This is fun!!!! Takes my mind off all that dumb pain

 

12z GFS in 4 hours 17 minutes

[Gradient Keeper]

6z GEFS Surface Temps
January 14th - 20th
Portland: 14-24 F, Cluster to 8-18 F
Seattle: 10-26 F, Cluster to 14-18 F
Yakima: -7 to 17 F, Cluster to -11 to 5 F

[Gradient Keeper]

6z GFS Ensembles

850mb Temps

 

 

Portland: Solid modified arctic blast! Mean temp -13c, Cluster to -15c. January 17th 850s warm to -5c, but there are several colder members through the 21st.

http://old.wetterzentrale.de/pics/MT8_Portland_Oregon_USA_ens.png

 

Seattle: Impressive Arctic blast! Mean temp -15.5c, Cluster to -17c. 850s do not warm to -5c until January 21st. Many cold members through the 22nd.

http://old.wetterzentrale.de/pics/MT8_Seattle_USA_ens.png

 

Yakima: MAJOR to Severe arctic blast: Mean temp -21c, Cluster to -24c. 850s do not warm to -10c until January 19th and -5c until the 21st. A lot of cold members to -15c through the 21st.

http://old.wetterzentrale.de/pics/MT8_Yakima_USA_ens.png

 

Vancouver BC: Solid arctic blast! Mean temp -16c, Cluster to -19c. 850s do not warm above -10c until January 17th and only reach -5c on the 23rd. Many cold members through the 22nd.

http://old.wetterzentrale.de/pics/MT8_Vancouver_Kanada_ens.png

[SilverFallsAndrew]

That run was so cold I do not really know what to say. 

 

I guess the only nit one could pick is cold = drier, but D**n that run was gorgeous. 

 

The trend on the ensembles is incredible too. 

[SilverFallsAndrew]

Portland AFD at least mentioning the possibility now...

 

Given the models are notorious for bringing cold air west of the
Rockies too easily and nearly every arctic intrusion ends up being a
bit warmer than initially advertised by the models (even 24-48 hours
in advance) and slower to arrive to our CWA, opted to cool
temperatures, but just not quite as fast and cold as the raw NBM
guidance. Nonetheless, there are a wide range of possibilities on the
table for early next week, which includes temperatures that are far
colder than the current forecast. /Neuman 

[SilverFallsAndrew]

CFS for the 31st... 1000-500mb thickness line of 504 is to about Eugene at this point.

 

[SilverFallsAndrew]

CFS keeps us locked in a generally cold and sometimes arctic pattern through the first 10 days of February. 

[Gradient Keeper]

CFS keeps us locked in a generally cold and sometimes arctic pattern through the first 10 days of February. 

Why not!

[FroYoBro]

Just saw last nights runs and the 06z.

 

Ok, I’m getting excited.

 

Going to be very interesting tracking lows/moisture along the cold boundary Sunday - Tuesday. Some surprises will surely show up as this all evolves.

[SilverFallsAndrew]

You still have to believe the aggressive CAA the GFS is showing is massively overdone.

[SilverFallsAndrew]

Approaching -40 this morning at Fairbanks. Nearing -50 at the typical cold spots of McGrath and Fort Yukon.

[FroYoBro]

You still have to believe the aggressive CAA the GFS is showing is massively overdone.

Of course, but the Euro keeps taking steps towards the GFS. It won’t be as cold as the 06z shows, but the chances of arctic air to Portland continue to increase!

[SilverFallsAndrew]

A couple things to watch/thoughts. 

 

1) Does the EURO continue trending colder. 

2) If models converge on an aggressive push of arctic air. Folks from Olympia north are going to really want to watch that Sunday system. I think that one is the big chance going into this for folks up north. 

3) The Monday low could be big for PDX and points south. The 06z GFS has it coming in WAY south, but most runs have had it coming in at a spot that is perfect for a big PDX snowstorm. I think the concern right would be does it slips south too fast and offshore flow takes over at PDX.

4) If any of these lows hang up/stall anywhere for a couple hours there is huge potential. 

5) If the arctic trough digs as aggressively as the GFS shows I think the mid-week system is going to go south. It may get close enough to spin up a deformation band north of the low, but if models continue to trend colder in the Monday-Wednesday period I would expect that low eventually ends up way south. If the arctic trough does not dig as much then a EURO like solution would be on the table. 

6) Watch for weak surface lows. There is going to quite a bit of arctic air interacting with the warm Pacific. It would not surprise me if we see weak surface lows developing off Vancouver Island and tracking south along the coast with this. These probably would be pretty late to pop up in the models. 

7) There are a lot of twists and turns ahead. I still think models will not lock in on a solution for the Sunday-Tuesday period until very late in the game. We will probably see wild fluctuations for the period after that. 

8) I think this has the potential to be a lengthy cold period.

[Prairiedog]

Everyone would be happy.

This will be interesting.  Last Feb the EURO got the amounts right but the location wrong as it shifted everything both north and south of us.  Really curious to see (and along with increasing model agreement among the others) if this will play out this way for the Valley.  Still a ways to go yet.  While things seem to be aligning favorably, still need to get inside a couple days before I do my snow dance.  Cold seems to be inevitable. 

[Prairiedog]

 

So busy looking at everything didn't even see this little gem.

 

January 8, 2020

 

I peek at the WRF now and then but hows it's track record?  Never really ran it side by side other models.  I always seem to forget about it.  Does it come anywhere close to the GFS or EURO? 

[SilverFallsAndrew]

I peek at the WRF now and then but hows it's track record?  Never really ran it side by side other models.  I always seem to forget about it.  Does it come anywhere close to the GFS or EURO? 

 

I believe they run it off the GFS. I believe it is supposed to have higher resolution than the operational GFS for instance. I have never been a huge fan, but some people swear by it. 

[FroYoBro]

The normies are going to start talking about it.

[Prairiedog]

Rod Hill has Tues at 33/24 and snow showers.  Time for Mark to test the waters.  He knows better not to jump too soon but it's inside his 7-day now. 

[Gradient Keeper]

Temps -40 or colder

 

Alaska
Chalkyitsik -51

Fort Yukon -49

Tanana -49

Nikolai -49

Allakakeet -48

Kaiyuh -48

McGrath -47

Umiat -45

Eagle -45

Bettles -44

Chena River -43

Kaltag -42

Selawik -41

Nenana -40

Fairbanks -40

 

Yukon

Satah River -49

Old Crow -45

 

Northwest Territories

Fort Good Hope -48

Rae Lakes -47

Norman Wells -47

Lac La Martre -45

[runninthruda206]

Wow, 6z was a crazy run. Wish it was a bit more snowy, but looks fun either way

[Gradient Keeper]

A couple things to watch/thoughts. 

 

1) Does the EURO continue trending colder. 

2) If models converge on an aggressive push of arctic air. Folks from Olympia north are going to really want to watch that Sunday system. I think that one is the big chance going into this for folks up north. 

3) The Monday low could be big for PDX and points south. The 06z GFS has it coming in WAY south, but most runs have had it coming in at a spot that is perfect for a big PDX snowstorm. I think the concern right would be does it slips south too fast and offshore flow takes over at PDX.

4) If any of these lows hang up/stall anywhere for a couple hours there is huge potential. 

5) If the arctic trough digs as aggressively as the GFS shows I think the mid-week system is going to go south. It may get close enough to spin up a deformation band north of the low, but if models continue to trend colder in the Monday-Wednesday period I would expect that low eventually ends up way south. If the arctic trough does not dig as much then a EURO like solution would be on the table. 

6) Watch for weak surface lows. There is going to quite a bit of arctic air interacting with the warm Pacific. It would not surprise me if we see weak surface lows developing off Vancouver Island and tracking south along the coast with this. These probably would be pretty late to pop up in the models. 

7) There are a lot of twists and turns ahead. I still think models will not lock in on a solution for the Sunday-Tuesday period until very late in the game. We will probably see wild fluctuations for the period after that. 

8) I think this has the potential to be a lengthy cold period.

Very good post and analysis. I would add one more. 9) Does the lobe of the PV dig right down over Washington. Models have trended it further and further to the southwest. If so, that would be a major driver to blast the coldest arctic blast we've seen I'm thinking since December 1990 if not February 1989. Based on that I really think historic cold is still on the table, but we need to see the EURO dig the trough more at Day 5-6. Maybe we will.

 

12z ECMWF in 3 hours 42 minutes

[ttt]

         

 

[runninthruda206]

I’d still take the trade off of more snow and a little less cold for Seattle but maybe that’s what the euro and gfs will converge on

[Gradient Keeper]

[Prairiedog]

It's about to get stupid around the PNW isn't it?

 

BRING IT ON!

I didn't have a chance to respond last night.  You are living in a time where medical technology has just exploded and medical conditions just a few years ago would have been much more difficult.  I spent part of the day yesterday at St. Vincent Hosp in Beaverton with an 89 year old woman who had been in my parents wedding party in '49, a dear friend.  She had a cow valve put into her heart.  She's going home today!  I visited with her both before and after her surgery and I couldn't see any difference in her pre surgery to post surgery.  She was eating, joking, and in an amazing state of health just hours later.  I was expecting days of recovery for her.  It was as if she never had the procedure (not what you'd expect from a post heart surgery patient) plus she can breath now.  Your situation is a bit different but my point is you're in amazing hands with amazing technology.  Godspeed my friend.   

[SilverFallsAndrew]

Probably start seeing Winter Storm Watches going up this evening. 

[Phil]

The AO index continues to be very positive going into this oncoming blast, proof we don't necessarily need tanking AO to get a blast in this region.

 

Many of the greatest US Arctic blasts (even in the East) occurred with +AOs. It helps to have it negative but really the surf activity and TPV structure matter more when it comes to severe cold anywhere in the mid latitudes.

 

As long as the TPV doesn’t couple to the strat via the +AO then it can be overcome.

[Phil]

WTF 06z GFS. Holy gawd d*mn that’s a full on TPV intrusion into the region.

[Phil]

[TT-SEA]

06Z EPS... which only goes out 144 hours... shows a quicker crash on Sunday as well.

 

I now think this is going to end up coming in like a freight train on Sunday evening through western WA.    The 006Z GFS showed the low racing from near Olympia at 10 a.m. to near Spokane by 4 p.m. and into Montana before midnight.    This low appears to to be the catalyst to pull cold air south in a hurry.

 

All of the things we laughingly said would not happen (like a flash freeze) are probably going to happen.   Nature is in charge.  

[Chewbacca Defense]

Positive splat test this morning in a brief shower on my way to work in Bellingham!!

 

I have been slammed at work the past week and have not been able to pay nearly as much attention to the models as I would have liked.  With the constant in depth analysis going on it would have been a great opportunity to better educate myself on interpreting the models.

 

Hopefully things will settle down next week and I can pick it up as we continue to ride the models and see where this goes. 

[jakerepp]

BACON STORM.png

Even my folks in Nampa get in on the bacon fun! Score!