February 2021 PacNW Weather Discussion

[Timmy Supercell]

Just now, TheNewCulverJosh said:

Just can't get that boundary close enough to you down there. Klamath Falls weather, albeit not nearly as cold, reminds me a lot of Anchorage weather.  It would snow in all points North, South, East, West, and not in Anchorage when I was there.

Complete opposite to 16-17, constantly battered with snow and even when it wasn't snowing, lots of moderate/heavy rainfall. Want that again!

[TheNewCulverJosh]

2 minutes ago, nwsnow said:

I like where we are sitting now. At least for NW OR and areas north, it is looking increasingly like to be either snowy or very cold and dry and hopefully snow later on. Nothing really indicating SW winds, 40s and/or rain. Gonna be fun to watch the models try to nail the exact track of this system. Hopefully in the coming 24 hours we will get some kind of consensus. I'm expecting things will eventually trend back north a bit but we can probably rule out any lows bombing out and flying to BC at this point.

Take it back to old school and watch this thing in real time, infrared and WV imagery.

[MR.SNOWMIZER]

4 minutes ago, wxmet said:

Special Weather Statement
National Weather Service Seattle WA
317 PM PST Mon Feb 8 2021

WAZ001-503-504-506-507-509>512-514>517-555-556-558-559-091130-
San Juan County-Western Whatcom County-Southwest Interior-
Western Skagit County-Everett and Vicinity-Tacoma Area-
Admiralty Inlet Area-Hood Canal Area-Lower Chehalis Valley Area-
Eastern Strait of Juan de Fuca-Western Strait of Juan De Fuca-
North Coast-Central Coast-East Puget Sound Lowlands-
Bellevue and Vicinity-Seattle and Vicinity-Bremerton and Vicinity-
317 PM PST Mon Feb 8 2021

...WINTRY WEATHER POSSIBLE LATER THIS WEEK FOR THE LOWLANDS OF WESTERN
WASHINGTON...

Cold air over British Columbia is likely to push south into
Western Washington this week. Fraser outflow into the Bellingham
area should increase--with cold wind chills by Thursday across
Whatcom county. Windy conditions are likely to affect the San
Juans islands as well--with northeasterly gales likely across the
waters by Thursday. Areas farther south and near the coast will
also see a cooing trend--but could avoid a hard freeze. After the
colder air arrives, a front might reach the area with a chance of
snow Thursday and Friday. Stay tuned to NOAA weather radio,
weather.gov, or your favorite source of weather information in the
days ahead as the forecast is updated.

We will get a screen shot of this from Randy in the year 2037

[Cloud]

4 minutes ago, wxmet said:

Special Weather Statement
National Weather Service Seattle WA
317 PM PST Mon Feb 8 2021

WAZ001-503-504-506-507-509>512-514>517-555-556-558-559-091130-
San Juan County-Western Whatcom County-Southwest Interior-
Western Skagit County-Everett and Vicinity-Tacoma Area-
Admiralty Inlet Area-Hood Canal Area-Lower Chehalis Valley Area-
Eastern Strait of Juan de Fuca-Western Strait of Juan De Fuca-
North Coast-Central Coast-East Puget Sound Lowlands-
Bellevue and Vicinity-Seattle and Vicinity-Bremerton and Vicinity-
317 PM PST Mon Feb 8 2021

...WINTRY WEATHER POSSIBLE LATER THIS WEEK FOR THE LOWLANDS OF WESTERN
WASHINGTON...

Cold air over British Columbia is likely to push south into
Western Washington this week. Fraser outflow into the Bellingham
area should increase--with cold wind chills by Thursday across
Whatcom county. Windy conditions are likely to affect the San
Juans islands as well--with northeasterly gales likely across the
waters by Thursday. Areas farther south and near the coast will
also see a cooing trend--but could avoid a hard freeze. After the
colder air arrives, a front might reach the area with a chance of
snow Thursday and Friday. Stay tuned to NOAA weather radio,
weather.gov, or your favorite source of weather information in the
days ahead as the forecast is updated.

So it begins. 

[TheNewCulverJosh]

1 minute ago, Timmy_Supercell said:

Complete opposite to 16-17, constantly battered with snow and even when it wasn't snowing, lots of moderate/heavy rainfall. Want that again!

I'm hoping to be in the sweet spot here with the low level northerly flow and deep overrunning moisture....fingers are crossed.

[Slushy Inch]

We'll probably know when the 18z Euro comes out, it could fold to the GSF.

[Perturbed Member]

PDX AFD

"there is some indication that air mass to south of Portland will stay too warm, with some southerly component aloft that may result in any snowflakes melting before reaching the ground. So, will trend to keeping snow levels around 500 feet for the Portland/Vancouver metro"

How does this even make any sense? The surface is all well below freezing in these areas, the warm nose is way above. If you get warm nosed, sea level or 500 ft doesn't really matter. NWS loves to pull arbitrary snow levels out of their rear ends. 

 

[bainbridgekid]

Those with access to the 18z Euro . . . Your updates would be greatly appreciated as it starts to come out after 4.

[TheNewCulverJosh]

2 minutes ago, nwsnow said:

PDX AFD

"there is some indication that air mass to south of Portland will stay too warm, with some southerly component aloft that may result in any snowflakes melting before reaching the ground. So, will trend to keeping snow levels around 500 feet for the Portland/Vancouver metro"

How does this even make any sense? The surface is all well below freezing in these areas, the warm nose is way above. If you get warm nosed, sea level or 500 ft doesn't really matter. NWS loves to pull arbitrary snow levels out of their rear ends. 

 

Yep, being near the freezer door or being in a location where cold air damming occurs is all that will matter with this one.  Obviously orographics will play a part to some degree say for the west hills and adjacent coast range foothills.  I wouldn't be surprised if someone up at Skyline sees 18".

[luvssnow_spokane]

11 minutes ago, GHweatherChris said:

Just caught this f**ker mocking me in our backyard, I chased him in to the woods, so we are good..... for now.

What was Jesse doing in your back yard? Rude!

[GHweatherChris]

10 minutes ago, jakerepp said:

Thank God you caught him in time!

I have my Red Ryder BB Gun locked and loaded, gonna sit in the dark and wait for that bastard tonight during the model runs!!

[paulb/eugene]

3 minutes ago, bainbridgekid said:

Those with access to the 18z Euro . . . Your updates would be greatly appreciated as it starts to come out after 4.

Where’s the Korean

[GobBluth]

7 minutes ago, nwsnow said:

PDX AFD

"there is some indication that air mass to south of Portland will stay too warm, with some southerly component aloft that may result in any snowflakes melting before reaching the ground. So, will trend to keeping snow levels around 500 feet for the Portland/Vancouver metro"

How does this even make any sense? The surface is all well below freezing in these areas, the warm nose is way above. If you get warm nosed, sea level or 500 ft doesn't really matter. NWS loves to pull arbitrary snow levels out of their rear ends. 

 

I think they toss out a snow level figure to keep it simplistic for the plebes.

[GHweatherChris]

5 minutes ago, bainbridgekid said:

Those with access to the 18z Euro . . . Your updates would be greatly appreciated as it starts to come out after 4.

Are you able to share the model ride with your students like you did last winter?  I thought that was pretty awesome!!

[bainbridgekid]

2 minutes ago, hawkstwelve said:

I'll trade you the 18z Euro (when it starts coming out here in a few) for the 18z NBM.

 

[Bryant]

26 minutes ago, wxmet said:

18z RGEM looks good for a regional event

There's a county up here that would like to be included in the fun please 

[bainbridgekid]

Just now, GHweatherChris said:

Are you able to share the model ride with your students like you did last winter?  I thought that was pretty awesome!!

Waiting to see how the models look tomorrow before I bring it up with them.

In February 2019 my students thought I might literally control the weather because we looked at it in so much detail and every time I mentioned my snow forecast it happened almost exactly as I said. Doesn't always work like that

[SilverFallsAndrew]

12 minutes ago, nwsnow said:

PDX AFD

"there is some indication that air mass to south of Portland will stay too warm, with some southerly component aloft that may result in any snowflakes melting before reaching the ground. So, will trend to keeping snow levels around 500 feet for the Portland/Vancouver metro"

How does this even make any sense? The surface is all well below freezing in these areas, the warm nose is way above. If you get warm nosed, sea level or 500 ft doesn't really matter. NWS loves to pull arbitrary snow levels out of their rear ends. 

 

I read that and it is idiotic. No wonder they are always blowing winter weather forecasts. 

[wxmet]

1 minute ago, Bryant said:

There's a county up here that would like to be included in the fun please 

 

It slowly works its way north and also improves temps down in PDX area. Win for most on here.

[Phil]

Something else about this pattern is it’ll help lower PMM/PDO. Look at what’s being advected out over the subtropical Pacific:

 

[BLI snowman]

12 minutes ago, nwsnow said:

PDX AFD

"there is some indication that air mass to south of Portland will stay too warm, with some southerly component aloft that may result in any snowflakes melting before reaching the ground. So, will trend to keeping snow levels around 500 feet for the Portland/Vancouver metro"

How does this even make any sense? The surface is all well below freezing in these areas, the warm nose is way above. If you get warm nosed, sea level or 500 ft doesn't really matter. NWS loves to pull arbitrary snow levels out of their rear ends. 

 

 

Right, the surface advection will determine where the frozen precip line is, and the upper level temps will determine the precip type. Not a marginal, elevation dependent situation at all. 

[TheNewCulverJosh]

Hopefully by tomorrow night we can start tracking the system vs. models.

[UWweathernerd]

Installing these to ensure no rugs are pulled from under our feet !!

[Phil]

3 minutes ago, BLI snowman said:

 

Right, the surface advection will determine where the frozen precip line is, and the upper level temps will determine the precip type. Not a marginal, elevation dependent situation at all. 

I don’t know, if WAA aloft affects crystal growth it could affect the melt rate and dynamic cooling potential. Depends how high up they’re talking, I guess?

[High Desert Mat?]

3 minutes ago, Phil said:

Something else about this pattern is it’ll help lower PMM/PDO. Look at what’s being advected out over the subtropical Pacific:

 

I would just like to say thank you SSW. Without you I doubt we’d be seeing a map like this. 

[TT-SEA]

14 minutes ago, bainbridgekid said:

Those with access to the 18z Euro . . . Your updates would be greatly appreciated as it starts to come out after 4.

Its out to hour 3 now... its really bad.   Winter cancel! 

[Phil]

3 minutes ago, High Desert Mat? said:

I would just like to say thank you SSW. Without you I doubt we’d be seeing a map like this. 

Yeah it’s interesting. You can actually track the deposition of momentum and both intraseasonal GWO/MJO cycles back to the inception of the SSW. These things have cascading impacts for months after they occur.

Without the SSW I suspect we’d have repeated 1999/00 or maybe 2007/08 at best.

[Meatyorologist]

18z so far ejects a bit more energy into that AK lobe. Could be a move north, but it's tough to say at this point.

[BLI snowman]

1 minute ago, Phil said:

I don’t know, if WAA aloft affects crystal growth it could affect the melt rate and dynamic cooling potential. Depends how high up they’re talking, I guess?

WAA aloft will only occur if the low goes north. In a situation such as this with such strong surface advection and a subfreezing column, there's no plausible scenario where 500' in Portland is seeing accumulating snow and the valley floor isn't.

[Phil]

Just now, BLI snowman said:

WAA aloft will only occur if the low goes north. In a situation such as this with such strong surface advection and a subfreezing column, there's no plausible scenario where 500' in Portland is seeing accumulating snow and the valley floor isn't.

Makes sense. Thank you.

[Phil]

18z Euro is a slight step back in the upper levels. Nothing horrible, just modest. 

[TheNewCulverJosh]

After 5 days of South, Southwesterly, or westerly winds we have now turned northerly here in Culver.  

[snow_wizard]

The offshore block is stronger on the 18z ECMWF.  Probably going to be a cold run.

[wxmet]

Upper level low is further north in the Pacific. Trough moving down the B.C. more or less in the same position compared to 12z out to 42hrs.

[BLI snowman]

Confricting reports

[snow_wizard]

3 minutes ago, hawkstwelve said:

High temps tomorrow.

Very likely too warm for Whatcom County.

[paulb/eugene]

My review of 18z euro thus far is that it suggests low later this week will track slightly farther north than on the 12z

[SilverFallsAndrew]

18z EURO is better and worse. 

[paulb/eugene]

[SilverFallsAndrew]

1 minute ago, paulb/eugene said:

My review of 18z euro thus far is that it suggests low later this week will track slightly farther north than on the 12z

Good news for W. WA. Devastating trends for southerners.