PNW December 2022, winter might be coming; but mostly canceled.

[TT-SEA]

Dumping south of Chehalis on I-5...

 

[TT-SEA]

Its 40 degrees in North Bend and 38 up here this morning with a gusty east wind.  And yet nothing is melting with a dewpoint in the low 20s.

 

[TT-SEA]

That large area of convective look precip around Chehalis is heading right for @GHweatherChris

[GHweatherChris]

3 minutes ago, TT-SEA said:

That large area of convective look precip around Chehalis is heading right for @GHweatherChris

Ya, it looks intriguing, I am at my work desk on one side of the room and using Bluetooth mouse to monitor weather things on our personal computer to my right lol.

[TT-SEA]

5 minutes ago, GHweatherChris said:

Ya, it looks intriguing, I am at my work desk on one side of the room and using Bluetooth mouse to monitor weather things on our personal computer to my right lol.

I do the same thing... personal computer right next to my work set up just for weather purposes.   Are you working today?

[GHweatherChris]

Just now, TT-SEA said:

I do the same thing... personal computer right next to my work set up just for weather purposes.   Are you working today?

Yep, til noon. but I have a big window next to me and a light outside to monitor live conditions.

[TT-SEA]

In terms of timing... the big show appears to be early afternoon per the ECMWF.    Moisture is just going to explode this morning.     That area of convective precip moving west now is just a precursor.

[TacomaWx]

Seeing a few flakes already…at 38 degrees. Temp will drop once heavier precip moves in. 

[TacomaWx]

[T-Town]

Streetlight check still negative here. 38 degrees. 

[FroYoBro]

Same conditions as when I went to sleep last night. 
38 degrees with a dp of 25. Unfortunately will take some time to wet bulb down to a snowier temperature. 

[TacomaWx]

1 minute ago, T-Town said:

Streetlight check still negative here. 38 degrees. 

Negative for now here as well. Did see some flakes a bit ago though. It’s interesting someone mentioned this earlier but this type of set up would be a thunderstorm outbreak in the summer time. This cell is taking a similar trajectory to the big thunderstorm that hit us on august 10th this year…just further south. Nice to see we’re included in the area for potential higher accumulation today! 

[The Blob]

38 IMBY and breezy

[Dave]

Surprisingly, I woke up to a dusting of snow. It appears to have transitioned to rain/freezing rain though. 33 degrees. The ground is crunchy.

[FroYoBro]

Nice to see the upper levels cool as the low approaches closer. All of the ugly red is gone from the western valleys now. 

[TacomaWx]

5 minutes ago, FroYoBro said:

Nice to see the upper levels cool as the low approaches closer. All of the ugly red is gone from the western valleys now. 

Kind of weird seeing cooler air aloft moving in from the south. 

[Dave]

It's quite unusual to have clouds coming out of the SSE, let alone having them deliver any frozen precip down here. Looks like the DPs around the northern WV are quite low. If some decent precip comes, you should be in business. Radar looks a little skinny though.

[Dave]

1 minute ago, TacomaWx said:

Kind of weird seeing cooler air aloft moving in from the south. 

You were reading my mind!

[Timmy]

Nam turning it up for pdx

[SilverFallsAndrew]

It’s over. 

[Dave]

2 minutes ago, SilverFallsAndrew said:

It’s over. 

R.I.P. snow. We hardly knew you.

DOB: 12/04/22 4:45AM

Died 12/04/22 5:15AM

[Gradient Keeper]

Temp: 36.3, Dewpoint: 24.7 with strong east winds and mostly cloudy skies.

[Gradient Keeper]

From the PDX NWS AFD "As of 5 AM, the NBM was showing a 20-40 percent chance of 2+ inches of snow through tonight in the Portland metro northward and west of I-5 southward to about Dallas. This is a significant increase from the probabilities shown 12-24 hours ago, and if some of the more aggressive models pan out with a persistent frontogenesis band over the metro area, we could see considerably more than 2 inches somewhere in the metro area from this event."

 

Hmmm....

[SilverFallsAndrew]

Went out to check since there are radar returns over us. Looks like a light sleet/snow mix. A dusting on the cars and bark dust. 

[FroYoBro]

11 minutes ago, Timmy said:

Nam turning it up for pdx

Looks like l will be slightly too far south for the bullseye, but will be happy if I can manage ANY sticking snow today. 

[GHweatherChris]

Got some kind of frozen precip falling here.

[Dave]

PDX NWS has supplied a visual aid for a potential warm tongue, which should result in it busting to everyone's delight.

 

[MossMan]

I can do this routine in my sleep after living here for almost 5 years now. Either someone hit ice and took out a pole, or a squirrel wanted to warm up its nuts and got cooked, or a really fat squirrel broke a branch over the power line. Anyway let’s see how many hours or days it will be this time! 

[The Blob]

I had flakes flying in the air when I left for work.

[Gradient Keeper]

Northern Oregon Cascades/Foothills temps

Clackamas County
Wanderers Peak(4350') 18
Horse Creek(3402') 25

Looking at RAP 4hr Trends/Forecasts
925s the 0c line is progressing westward towards PDX metro
850s over the Willamette Valley and PDX metro have cooled from +1 to +2c over the past 4 hours now -0c to -1c.
The next 4-6 hours 925s 0c line is progged to push south to about Salem and 850s -2c to about Salem and -3c just east of Portland.

Based on the current observations it seems the air mass is cooling aloft to support sleet/snow and seeing no signs of any warming southerly push up along the Foothills anywhere even well south down to Douglas County.

[TacomaWx]

C’MON 

[Gradient Keeper]

A rather stout Columbia Basin cold pool remains intact with 925s -3c to -5c. This will keep supplying colder, drier air through the Gorge as long as the east wind continues. The maps below are 925mb, 850mb.

 

[Gradient Keeper]

7 AM Cold pool just deepened a bit further.

[Gradient Keeper]

7:10 AM Radar Update

Moisture increasing as lift increases.

[The Cats Meow]

31 here in the valley

no snow or rain yet

[Gradient Keeper]

Temp: 36.5, Dewpoint: 22.8 cloudy with intermittent flurries. Gusty east wind continues.

[Blizzard777]

36* with dp 27. It did get down to 33* at 12am with clouds clearing off. 

Winds NNW at 10. Current nest cam showing the band of moisture to my west 

[snow maniac]

Mixed precipitation here. Look’s icy 

[GHweatherChris]

Phat flakeage mixing in.

[snow maniac]

Now sleet, sounds like a hail storm outside