Part I - January 2020 Weather Discussion for the PNW

[Perturbed Member]

Well, it is closer in time, so that feels a bit more real to me.

 

Hard to say still. I think there is some decent potential with that low. 

 

GFS shows a snow in the air scenario from about Monday evening. Soundings show it won't really even be close to sticking. Temps plummet into the 20s on the backside of the low and there is still some precip left. Enough for light accumulations potentially. The NAM shows the cold coming in way faster but we know its cold bias, I think the GFS solution is probably the realistic one. 

 

Snow in the air and once it is getting real cold, precip becomes more spotty. We know this scenario is the norm here. It does certainly have the potential for surprises though.

[SilverFallsAndrew]

Watching live coverage out of Oklahoma as there are active tornado warnings. Tonight snow is expected with winter storm warnings posted for the northern counties. 

[Frontal Snowsquall]

12z UKMET days 4-6.

 

http://img.meteocentre.com/models/ukmet_amer_12/GZ_D5_PN_096_0000.gif

http://img.meteocentre.com/models/ukmet_amer_12/GZ_D5_PN_120_0000.gif

http://img.meteocentre.com/models/ukmet_amer_12/GZ_D5_PN_144_0000.gif

[runninthruda206]

I don’t even care about that mid week low until we get past Monday. I just want a huge c zone in Seattle Sunday night! Will help with everything including colder temps

[MR.SNOWMIZER]

Don't even worry about warming yet next weekend. Just pick a hr on the models and click back 6 runs and watch the variables. Pretty interesting really. 2008 had this happen time and time again. Traditional cold spells end in a good overrunning event so that would be cool to see.

[Perturbed Member]

12z ICON came in wetter with a stronger system. As long as the EURO/EPS keep showing a lot of precipitation then I think we'll be okay.

 

 

 

Not sure how much we should even trust the ICON

 

It is massively warmer than the other models, not sure what is going on with it

 

 

[SilverFallsAndrew]

GFS shows a snow in the air scenario from about Monday evening. Soundings show it won't really even be close to sticking. Temps plummet into the 20s on the backside of the low and there is still some precip left. Enough for light accumulations potentially. The NAM shows the cold coming in way faster but we know its cold bias, I think the GFS solution is probably the realistic one. 

 

Snow in the air and once it is getting real cold, precip becomes more spotty. We know this scenario is the norm here. It does certainly have the potential for surprises though.

 

I think someone between PDX and Roseburg will see 2-4" to the lowest elevations with that Monday evening system. 

[TacomaWaWx]

These next couple days will be interesting to see the actual acrtic air racing out of Alaska through BC. Should be some fun model riding trying to pin down the details past Monday too. Nothing set in stone in the mid to long range.

[GHweatherChris]

Not sure how much we should even trust the ICON

 

It is massively warmer than the other models, not sure what is going on with it

 

 

Ya, I dont think the Icon or UKMET maps need to be posted, they are worthless.

[El_Nina]

Sunday night is maybe the first chance of snow here. A dusting looks possible as the backside precip moves through the foothills. I'd be more confident if I were 400' higher but we'll see. Monday or Monday night I have a fairly good feeling about and the rest of the week isn't worth commenting on yet.

[SilverFallsAndrew]

GFS long range is just normal valley rain and mountain snow. 

[Omegaraptor]

These next couple days will be interesting to see the actual acrtic air racing out of Alaska through BC. Should be some fun model riding trying to pin down the details past Monday too. Nothing set in stone in the mid to long range.

 

It's not "will the event happen" anymore, it's now "what exactly will happen" and will be "when will the event end" soon. Let's hope that low shown on some of the GFS runs doesn't materialize so the cold can last.

[SilverFallsAndrew]

Sunday night is maybe the first chance of snow here. A dusting looks possible as the backside precip moves through the foothills. I'd be more confident if I were 400' higher but we'll see. Monday or Monday night I have a fairly good feeling about and the rest of the week isn't worth commenting on yet.

 

Sunday afternoon has trended a lot cooler for the foothills of NW Oregon. Looking at the 12z I would estimate precip turns over to all snow here between noon-2pm Sunday. Looks pretty juicy Sunday evening too. I would say 2-4" of snow are a good bet up here Sunday PM/early Monday AM. 

[Cloud]

Not sure how much we should even trust the ICON

 

It is massively warmer than the other models, not sure what is going on with it

 

 

ICON is showing the Sunday system here well north into BC at Hour 60, when the other models are similar with the tracks much more south. I sure as hell won’t trust it at hour 120

[Omegaraptor]

Not sure how much we should even trust the ICON

 

It is massively warmer than the other models, not sure what is going on with it

 

 

 

We don't look at the ICON the 98% of the time there's no major snow event forecast. Wonder why?

[Frontal Snowsquall]

Not sure how much we should even trust the ICON

 

It is massively warmer than the other models, not sure what is going on with it

 

 

Yeah, I dont think it can see the Gorge influence all that well. Never seen it do well in outflow situations.

[Rubus Leucodermis]

I have been consistently buried in that Sunday/Monday storm with pretty much every model run over the past few days. Much better than last February when every run showed me cold and dry while Puget Sound was getting pummeled (and the models were right).

 

Yes, the model runs have been most favorable for Whatcom/BCLM on Sunday. NWS now says 4-7" is likely for me. If that materializes, take the wind into account and it’s a genuine blizzard. We shall see.

 

[El_Nina]

Sunday afternoon has trended a lot cooler for the foothills of NW Oregon. Looking at the 12z I would estimate precip turns over to all snow here between noon-2pm Sunday. Looks pretty juicy Sunday evening too. I would say 2-4" of snow are a good bet up here Sunday PM/early Monday AM.

 

You must be dreading all the upcoming satellite dish clearoffs

[TT-SEA]

WRF appears to show less snow for Sunday evening here compared to the 00Z run.

[Perturbed Member]

Yeah, I dont think it can see the Gorge influence all that well. Never seen it do well in outflow situations.

 

I mean the ICON never really even shows much cold air advection into our region in the first place. It goes wrong long before hour 120. The Dalles is 17F warmer on the ICON as the Wednesday storm approaches as compared to the GFS. The ICON is completely on crack. 

[GHweatherChris]

It's not "will the event happen" anymore, it's now "what exactly will happen" and will be "when will the event end" soon. Let's hope that low shown on some of the GFS runs doesn't materialize so the cold can last.

Seems to me we should just worry about the end now and hope it gets here soon, according to some on here.

[SilverFallsAndrew]

You must be dreading all the upcoming satellite dish clearoffs

 

Yeah, it gets ridiculous. We had a sloppy 1" the other night and I had to go out and clear the dish 3 times. 

[Blizzard777]

Not much time to read and study maps this morning.  
Still in PDX and south winds picking up a bit.

Brother( who just signed up with the forum) on his way to get me.  We’re heading to the coast for a little high tide storm watching.  
fun weather is happening now!!! 

[Omegaraptor]

Spring is only 7 weeks away!!!

[Deweydog]

Anyone have a sun angle update?

[jakerepp]

Anyone have a sun angle update?

Getting higher. 

[Frontal Snowsquall]

12Z UKMET track of the midweek system.

 

[SilverFallsAndrew]

It feels like some people on here expect this cold spell to last a historic amount of time or expect a historically large snowstorm in their city.

 

Those things are always unlikely. (That's what makes them historic) A great week of potential is shaping up though, just try to enjoy it! 

 

Well we all know about my weenie freakout a couple days ago. I think many of us build up expectations based on the most extreme model runs. We know those outcomes are unlikely, but we hope everything else trends that way. I think a reasonable expectation would be most places along the I-5 corridor getting 5"+ from EUG up to BLI and maybe 2 sub-freezing highs at PDX, same for Seattle. We could do better than that, but even that outcome seems pretty good to me. 

[runninthruda206]

WRF appears to show less snow for Sunday evening here compared to the 00Z run.

Do you mind posting a pic or pointing me in the direction to take a look? Thanks!

[Omegaraptor]

Well we all know about my weenie freakout a couple days ago. I think many of us build up expectations based on the most extreme model runs. We know those outcomes are unlikely, but we hope everything else trends that way. I think a reasonable expectation would be most places along the I-5 corridor getting 5"+ from EUG up to BLI and maybe 2 sub-freezing highs at PDX, same for Seattle. We could do better than that, but even that outcome seems pretty good to me. 

 

PDX hasn't seen a subfreezing high since January 2017. Having two of them would still be great.

[El_Nina]

Yeah, it gets ridiculous. We had a sloppy 1" the other night and I had to go out and clear the dish 3 times.

 

I'm not sure if that's serious or if you're going along with my satellite dish joke.

[SilverFallsAndrew]

GEM trending south with the low Monday, but still way further north than the other models. 

[SilverFallsAndrew]

I'm not sure if that's serious or if you're going along with my satellite dish joke.

 

That is what Jesse always says about me...You just never know.

[runninthruda206]

Yeah it cut back a little bit. Still looks nice for you though.

 

Boooo. I don’t believe it though. With a c zone I’m sure there’ll be a lot more in central sound

 

On a positive note, recent models have shown it setting up over north Seattle which would be beautiful

[El_Nina]

That is what Jesse always says about me...You just never know.

Okay now I do

[luvssnow_spokane]

Anyone have a sun angle update?

Not good. Will not help our Phantom snow situation.  <_ src="%7B___base_url___%7D/uploads/emoticons/default_unsure.png" alt=":unsure:"> 

[SilverFallsAndrew]

GFS ensembles are coming in further south with the mid-week low. The mean on the 06z rose to -2.3C on the 16th, this run it only rises to -4.0C. 

 

Mean bottoms out at -11.3C, a little warmer than the 06z. Overall through the 16th though it trended slightly cooler for PDX. 

[luvssnow_spokane]

GEM says screw you guys - you all get rain!

 

GEM speaks truth. God bless it.

[Frontal Snowsquall]

[TacomaWaWx]

Taking a closer look at the WRF, it shows temps (850, 925, and surface) all being cold enough to support snow around 4PM Sunday. The problem is precip dries up incredibly fast, to the point where by 7PM it's pretty much done.

 

I think there will be some surprises and more snow will actually fall than being modeled. Wouldn't be the first time it happened.