February 2017 Observations and Model Discussion for the Pacific Northwest

[Perturbed Member]

Our best windows for sticking snow are probably 3-9pm and 1-3am. Everything points to a warm tongue in the late evening that switches us to rain.

Ouch. The warm tongue has been moving further and further NW from the low trending north. 

http://www.tropicaltidbits.com/analysis/models/gfs/2017020500/gfs_T850_nwus_6.png

[dairyd]

Everything is looking good. Trough is merging south just like the models are calling for. South stream low is moving almost due East, a little ESE. I just don't see how it can possibly move north of Portland based off WV loop.

 

Anyone want to contradict that?

Looking at the current and forecast jet pattern for the next 2 days, I don't think it is going to matter which low passes where, the energy and moisture flow is going to be widely dispersed between the two lows.

 

http://squall.sfsu.edu/gif/jetstream_pac_init_00.gif

[MossMan]

00Z GFS is great for precip up here... but the 850mb temp is noticeably warmer than the 12Z run. Not a good sign.

Rain for all!!

[seattleweatherguy]

00Z GFS is great for precip up here... but the 850mb temp is noticeably warmer than the 12Z run. Not a good sign.

Yikes let's hope the euro diesnt trend that way

[SilverFallsAndrew]

Man, Andrew really got to you all earlier.

 

What I did was touch on those seeds of doubt. Triggers a very instinctual defense mechanism. Psychology 101 there... 

[bainbridgekid]

Nearly a perfect track for Seattle on the 00z GFS.

 

Shows a solid 6-8" thump between about 8 PM and 10 AM.

[SilverFallsAndrew]

At this point the Hrrr is really on its own....

 

http://weather.graphics/hrrr/2017020502/washington/hrrr_snow_washington_19.png

[BLI snowman]

Ouch. The warm tongue has been moving further and further NW from the low trending north.

http://www.tropicaltidbits.com/analysis/models/gfs/2017020500/gfs_T850_nwus_6.png

Yeah, gonna be hard to get accumulations if that verifies. The wraparound stuff looks like our best shot, but it's a brief window there in the early morning.

[Perturbed Member]

00Z GFS is great for precip up here... but the 850mb temp is noticeably warmer than the 12Z run.    Not a good sign.   

Trade off for having the low further north. 

[MR.SNOWMIZER]

00Z GFS is great for precip up here... but the 850mb temp is noticeably warmer than the 12Z run.    Not a good sign.Might not matter much with all the seepage from the frazer?

 

[snow_wizard]

Ah the only true warm nose situation is in an overrunning scenario, more like warm side of the anafront lol

 

I get warm nosed sometimes too.  Totally sucks.

[Guest Dome Buster]

Yep. Just like yesterday's low went where models prognosticated. "sarcasm". There is such model riding on here it is ridiculous sometimes.

 

This winter has proven that nothing can be trusted. Sometimes within 2 hours.

[Perturbed Member]

Yeah, gonna be hard to get accumulations if that verifies. The wraparound stuff looks like our best shot, but it's a brief window there in the early morning.

Yeah, the northward trend across every single model just can't be ignored. This thing already looked really marginal to begin with. I will be impressed with any half decent snow we get out of this.

[luvssnow_spokane]

As I have (and a few others) shared earlier.. being to warm for sticking will be a huge factor. I am not surprised to see the model swings at all. Low expectations for this event makes this a non-issue for me.

[snow_wizard]

I'm not big on here but you'd think a possible almost region wide snow event would help bring everyone here together but it seems to be doing the opposite.

 

 

It is sad in a way.  Everyone gets so worked up they get grouchy.  As for myself I will feel a huge sense of relief to finally get this snow monkey off my back.  The last 5 years have been horrible here.

[MR.SNOWMIZER]

Starting to look like a possible major puget sound snow event. The biggest and deepest snow storms here have been marginal temp wise.

[Guest Dome Buster]

We need some cold air density from the gorge. For sure.

[SilverFallsAndrew]

Yep. Just like yesterday's low went where models prognosticated. "sarcasm". There is such model riding on here it is ridiculous sometimes.

 

This winter has proven that nothing can be trusted. Sometimes within 2 hours.

 

Really anything could happen. I would feel pretty confident if I lived between Kelso and Olympia. If I was Vancouver to Kelso and Olym to Seattle I would be cautiously optimistic. 

[luvssnow_spokane]

Yeah, the northward trend across every single model just can't be ignored. This thing already looked really marginal to begin with. I will be impressed with any half decent snow we get out of this.

For some, specially my area it will not be much compared to some of the ridiculous snow amounts have been spitting out. I will be happy with a couple inches but the 8 to 10 inches here is just not going to happen.

[snow_wizard]

As I have (and a few others) shared earlier.. being to warm for sticking will be a huge factor. I am not surprised to see the model swings at all. Low expectations for this event makes this a non-issue for me.

 

 

I think precip intensity will really be our friend on this one until the colder air really arrives tomorrow night.

[ShawniganLake]

Abbotsford was officially up to 15" of snow as of 4pm and there's been a fair amount more there since then with more coming in. Could be another 5~10" there overnight into tomorrow. It's pretty incredible what places with good proximity to the Fraser Valley outflow can do in a pattern like this. Here in Victoria, about 100 miles to the SE we only ended up with 1.5" and as of this afternoon it's completely melted. The outflow is shallow and just can't cross the Strait.

Snowed on and off all day up here. I haven't measured. Looks like 4-5" for today. Heavy wet stuff.

[snow_wizard]

For some, specially my area it will not be much compared to some of the ridiculous snow amounts have been spitting out. I will be happy with a couple inches but the 8 to 10 inches here is just not going to happen.

 

I'm really curious why you think this.

[luvssnow_spokane]

Starting to look like a possible major puget sound snow event. The biggest and deepest snow storms here have been marginal temp wise.

Uhhhhmmmm ... it has always been marginal temps wise. Nothing has changed other than the fact it is going beyond marginal to rain or non-sticking snow...

[Jesse]

It's the fork that takes you to either Kendal/back to Sumas or Glacier/mt Baker

I've probably seen it driving to Artist Point then.

[Guest Dome Buster]

Really anything could happen. I would feel pretty confident if I lived between Kelso and Olympia. If I was Vancouver to Kelso and Olym to Seattle I would be cautiously optimistic.

 

That's fair. You really are a voice of reason on here Andrew. I can appreciate that.

 

It's amazing how a 20 mile shift will really affect things tomorrow. It reminds me of watching yesterdays low wobble around and not go "where" it was forecast. Kind of like hurricanes do.

 

Maybe instead of watching these models we should have a "cone" forecast like they do for hurricanes. A lot of these pacific lows act the same way.

[Front Ranger]

Really anything could happen. I would feel pretty confident if I lived between Kelso and Olympia. If I was Vancouver to Kelso and Olym to Seattle I would be cautiously optimistic. 

 

Given the trend, I don't see any reason to put places south of OLM in a higher confidence window.

[dairyd]

anyone else notice the -22mb bli-ywl pressure gradient forecast on the 00z gfs for sunday night?  That will be the highest of the winter.  Looks like a blizzard setup...a 96 repeat?

[ShawniganLake]

Looks like El Niño is coming back for next season...so yes we are screwed next year. I'm hoping we can salvage this February since it has been one painful winter for us.

You know November 2006 was a Nino winter, right?

[SilverFallsAndrew]

That's fair. You really are a voice of reason on here Andrew. I can appreciate that.

 

It's amazing how a 20 mile shift will really affect things tomorrow. It reminds me of watching yesterdays low wobble around and not go "where" it was forecast. Kind of like hurricanes do.

 

Maybe instead of watching these models we should have a "cone" forecast like they do for hurricanes. A lot of these pacific lows act the same way.

 

Given the trend, I don't see any reason to put places south of OLM in a higher confidence window.

 

I remember the anafronts of March 13th and March 21, 2012. They both ended up about 50-75 miles off from where they were predicted to focus...

[SilverFallsAndrew]

I think there is a higher chance than anyone would like to acknowledge that the deformation band sets up much further NW of where the models are showing and a smaller chance it sets up much further south....

[luvssnow_spokane]

I'm really curious why you think this.

Overall, temps will be to warm tomorrow for much of the time. Continued warm nosing which I have seen progressing for many runs now. Timing of precip is more in line when the airmass it to warm. I am only speaking for my location btw not yours but I do not see the significant snow totals the models show. I think the problem here is people get so snow map focused they have a hard time seeing the real elephant in the room. I want to be wrong but I think the NWS has the right call on snow totals.

[snow_wizard]

anyone else notice the -22mb bli-ywl pressure gradient forecast on the 00z gfs for sunday night?  That will be the highest of the winter.  Looks like a blizzard setup...a 96 repeat?

 

All of that snow on the ground.  It's going to be insane up there!  The ice loaded trees could be disastrous too.

[snow_wizard]

Overall, temps will be to warm tomorrow for much of the time. Continued warm nosing which I have seen progressing for many runs now. Timing of precip is more in line when the airmass it to warm. I am only speaking for my location btw not yours but I do not see the significant snow totals the models show. I think the problem here is people get so snow map focused they have a hard time seeing the real elephant in the room. I want to be wrong but I think the NWS has the right call on snow totals.

 

I think you're wrong.  The 0z snowfall maps show 1 inch more than the 18z.  Fabulous surface pressure setup for low level CAA also.  850s are cold enough.

 

It shows us getting hammered with a period of very heavy snow tomorrow night.

[Guest Dome Buster]

I think there is a higher chance than anyone would like to acknowledge that the deformation band sets up much further NW of where the models are showing and a smaller chance it sets up much further south....

We just need seriously heavy precip rates. I lived in Lake Stevens, WA(NE of Everett) for 9 years. When we got socked in the PSCZ for hours sometimes, the temp would drop from 50 to 30 within an hour or two, then snow a quick 4 inches. Happened at least 6-8 times while I lived there, all from heavy precip. Meanwhile Lynnwood would be 45 with light rain showers.

[BLI snowman]

I think there is a higher chance than anyone would like to acknowledge that the deformation band sets up much further NW of where the models are showing and a smaller chance it sets up much further south....

Indeed. If the models are off then it'll be because they're too far south, not the other way around.

[TT-SEA]

WRF shows the warmer nose moving right up to King County tomorrow night.

 

Northward trend is no longer our friend.  This is noticeably warmer tomorrow night than the 12Z WRF.  

 

[luvssnow_spokane]

I think you're wrong. The 0z snowfall maps show 1 inch more than the 18z. Fabulous surface pressure setup for low level CAA also. 850s are cold enough.

 

It shows us getting hammered with a period of very heavy snow tomorrow night.

Well I hope you're right! . But I am very doubtful. I will buy you a beer if your right.

[Jesse]

Indeed. If the models are off then it'll be because they're too far south, not the other way around.

I've made peace with the fact that I probably won't see much of anything in regards to accumulation tomorrow.

[MR.SNOWMIZER]

WRF shows the warmer nose moving right up to King County tomorrow night.

 

Northward trend is no longer our friend.

 

Not going to matter with the pressure gradient we have.

[GHweatherChris]

WRF shows the warmer nose moving right up to King County tomorrow night.

 

Northward trend is no longer our friend.

 

Still looking good here, which is all that matters!!