February 2017 Observations and Model Discussion for the Pacific Northwest

[HighlandExperience]

ITs snowing here!!!!! OMG!

Snow or flurries?

[luvssnow_spokane]

YAH!!! 

 

[MossMan]

Coming down good. 31 degrees.

But air too dry...temps too warm...precip rates much too light...wasn't that the call from the pro's today calling for just some light rain or a mix?!

[HighlandExperience]

But air too dry...temps too warm...precip rates much too light...wasn't that the call from the pro's today calling for just some light rain or a mix?!

Seattle NWS says cold rain rest of week

[luvssnow_spokane]

Snow or flurries?

It was dumping... This fell in a few min... Temp fell from 37 to 33 in less than 5min

 

[TT-SEA]

ITs snowing here!!!!! OMG!

 

It will melt!   As you remind us all the time.  

[MossMan]

Seattle NWS says cold rain rest of week

And weekend and next week...followed by warm rain later in the week...they like their rain!

[Perturbed Member]

So both the RPM and WRF want to give the whole Willamette valley a good snowstorm Sunday as well.  This map obviously doesn't go far out enough to include all of the snow that should fall further north.

 

http://www.atmos.washington.edu/wrfrt/data/2017020300/images_d2/msnow24.96.0000.gif

 

 

The reason is pretty clear now, high precip rates creating an isothermal profile

 

http://www.atmos.washington.edu/mm5rt/data/current_gfs/images_d2/kpdx.81.0000.snd.gif

[luvssnow_spokane]

It will melt!   As you remind us all the time.  

[VancouverIslandSouth]

Coming down good. 31 degrees.

 

Definitely a good sign that you're seeing snow in an area where the 0z WRF showed virtually nothing. Another strike on the reliability of these snow maps:

 

http://www.atmos.washington.edu/wrfrt/data/2017020300/images_d3/wa_snow48.48.0000.gif

[bainbridgekid]

Apparently the WRF was just updated in the last couple days to try to correct the bias to push low level cold air out to quickly.

 

Cliff Mass mentioned that it would likely have a huge impact on snowfall predictions around the Columbia Gorge.

 

I'd take tonight's snow maps for Western Oregon with a larger than usual grain of salt as it could easily be an overcorrection.

[Perturbed Member]

ITs snowing here!!!!! OMG!

 

Is this real life?

[TT-SEA]

Apparently the WRF was just updated in the last couple days to try to correct the bias to push low level cold air out to quickly.

 

Cliff Mass mentioned that it would likely have a huge impact on snowfall predictions around the Columbia Gorge.

 

I'd take tonight's snow maps for Western Oregon with a larger than usual grain of salt as it could easily be an overcorrection.

 

Wow... that is huge news.   Very nice.   Now they need to fix its under-estimation of inversions as well.  

[Alex_Snakes]

Snowing in Tacoma

[SilverFallsAndrew]

Looks a lot like March 2012...That snow map does at least lol

[bainbridgekid]

My sister lives in Tacoma and said it's snowing and there's "a thin layer on the ground."

 

She's at about 400 feet.

[epiceast]

Definitely a good sign that you're seeing snow in an area where the 0z WRF showed virtually nothing. Another strike on the reliability of these snow maps:

 

http://www.atmos.washington.edu/wrfrt/data/2017020300/images_d3/wa_snow48.48.0000.gif

It shows snow over Chehalis gap which is similar terrain to Kitsap Peninsula. So it's not that far off.

[snow_wizard]

I really like the setup shown on the WRF for Sunday night / Monday morning. A low tracks from SW to NE and stays south / east of the Seattle area. Good backwash behind the surface low opens the flood gates on the cold air poised just to our north which really aids in CAA along with decent snowfall. Looking really good at this point.

 

I can't help but wonder if the NWS is going for the reverse the psychology mode on this thing. They have to know this has a good chance of working out.

[MR.SNOWMIZER]

Dumping here. Easy 1/2 inch.

[seattleweatherguy]

So chances low tonight and better sun into monday

[luvssnow_spokane]

All done here but it was glorious. 

[Dave]

Could snow_wiz or PullyallupJon be getting snow flurries as well?  The silence is deafening.

[Perturbed Member]

Looks a lot like March 2012...That snow map does at least lol

 

Yep lol.

http://www.atmos.washington.edu/wrfrt/data/2017020300/images_d1/s_pcp24.84.0000.gif

[epiceast]

Next band looks a little stronger and less organized. Could be muy bueno for someone in 3 hours.

[snow_wizard]

Could snow_wiz or PullyallupJon be getting snow flurries as well?  The silence is deafening.

The band is almost here. Might get quick flurry. I'm already seeing some evaporative cooling taking place.

[luvssnow_spokane]

Could snow_wiz or PullyallupJon be getting snow flurries as well?  The silence is deafening.

Yes for PuyallupJon  possible for the wiz... Looking at radar it is possible but the east wind component where he lives "might" make it tougher, specially since precipitation rates are not real heavy. 

That being said I am not expecting any to much accumulation tonight, it as just nice to see it falling. I was thinking the dry air would zap out the moisture before it would hit the ground.

[TT-SEA]

The band is almost here. Might get quick flurry. I'm already seeing some evaporative cooling taking place.

 

The band is pretty much past you now.   Almost past my house as well.  

[Dave]

The band is almost here. Might get quick flurry. I'm already seeing some evaporative cooling taking place.

If anyone deserves a few flakes, it is you.  Come on snow gods, deliver!

[Bryant]

Definitely a good sign that you're seeing snow in an area where the 0z WRF showed virtually nothing. Another strike on the reliability of these snow maps:

 

http://www.atmos.washington.edu/wrfrt/data/2017020300/images_d3/wa_snow48.48.0000.gif

This map hurts to look at. I'm literally 5 miles south of the snow line there

[Perturbed Member]

Wow... that is huge news.   Very nice.   Now they need to fix its under-estimation of inversions as well.  

 

So I need to retract my bashing of the WRF somewhat. If you look at the standard "snowfall" map, it incorrectly shows snow for PDX tonight  even though that is impossible with the warmer air aloft. However if you look at "model snowfall", it correctly accounts for the air profile. Mark Nelsen posted about this a few minutes ago. 

 

It seems the regular snowfall map works fine usually but it spits out total nonsense when dealing with inversions. Does it just base precip type based on surface temp? I doubt it would be that dumb. 

[Bryant]

If anyone deserves a few flakes, it is you. Come on snow gods, deliver!

Tim is using all of his will power to keep snow out of Covington right now.

[VancouverIslandSouth]

It shows snow over Chehalis gap which is similar terrain to Kitsap Peninsula. So it's not that far off.

 

Much of it was forecast later on, and it looks a lot more widespread on the radar than that would indicate. I wouldn't be surprised if this overrun turns out to be a bit more moisture rich than forecast and more areas in the snowless zone on the WRF end up with 1/2"+. This system started its life over a region of subtropical ocean afterall.

[luvssnow_spokane]

Next band looks a little stronger and less organized. Could be muy bueno for someone in 3 hours.

Yes it looks pretty strong... Fun to watch it and see if it holds together and/or strengthens. Here is it as now:

 

[snow_wizard]

Seeing a little bit of light snow right now. It's pretty windy so it's just blowing around.

 

On another note Monday looks amazing for the Seattle area. Solidly cold and snowy on the WRF. the WRF shows two good surges of cold for the Seattle area...one on Monday and the other on Wednesday.

[Bryant]

Seeing a little bit of light snow right now. It's pretty windy so it's just blowing around.

 

Good to hear

[Dave]

Tim is using all of his will power to keep snow out of Covington right now.

You don't know the power of the Tim side.

[HighlandExperience]

Light snow falling in Renton according to a good friend

[TT-SEA]

GFS MOS for SEA:

 

Fri  47

Sat  49

Sun  46

Mon  42

Tues  45

 

That truly makes me doubt the WRF.     You cannot discount the GFS MOS.   Its the gut check for these events... seen it many times.  

[crf450ish]

Yes for PuyallupJon  possible for the wiz... Looking at radar it is possible but the east wind component where he lives "might" make it tougher, specially since precipitation rates are not real heavy. 

That being said I am not expecting any to much accumulation tonight, it as just nice to see it falling. I was thinking the dry air would zap out the moisture before it would hit the ground.

 

I'm quite positive PuyallupJon has checked out for the season. It'll take quite the snow storm at his place before this place sees the likes of him.

[luminen]

Tim is using all of his will power to keep snow out of Covington right now.

 

Borderline Satanic imo.

 

Jim more than deserves a 10"+ snowfall.