PNW Weather Discussion - December to Remember 2025

[TT-SEA]

47 minutes ago, Everleigh said:

31.8° 31.0°dp Radar shows precipitation over me, but muh eyeballs say different. 

Edit: Guess I needed to give it a minute. Flashlight test says Rain. 31° rain.  

There is still some frost in the shade part of the yard from yesterday morning and some raindrops falling on it.   

[Andstorm]

6 hours ago, Gradient Keeper said:

I'm trying to find a website where past computer model runs of the ECMWF and GFS are archived. I want to see what the computer models looked like December 1-4, 2008. Anyone?

I definitely second this request! Would be really fun to be able to go back, especially when things aren't looking particularly promising in the near term. 

[selkirks]

Raging zonal in early December is classic Niña but I’m worried about temps for mountain snow, at least at pass level and at Crystal—both of them are right at the cusp here. Another 20 years of warming and the ski resorts are gonna be toast.  

[Edmonds Husky]

Looks like the 12z GFS caved closer to the EURO/GEM camp. Garbage model lol

Edited December 1, 2025 by Edmonds Husky

[the_convergence_zone]

7 hours ago, Gradient Keeper said:

I'm trying to find a website where past computer model runs of the ECMWF and GFS are archived. I want to see what the computer models looked like December 1-4, 2008. Anyone?

Sadly it doesn’t exist. Only the initialization is archived. So you would have to re-run the model. There are some groups that are trying to make that easier for the average person but it’s costly. 

[MossMan]

4 minutes ago, the_convergence_zone said:

Sadly it doesn’t exist. Only the initialization is archived. So you would have to re-run the model. There are some groups that are trying to make that easier for the average person but it’s costly. 

If we could dig up the forum thread from December 2008 we could see what it was looking like…Sure wish there was a way. 

[Edmonds Husky]

1 minute ago, MossMan said:

If we could dig up the forum thread from December 2008 we could see what it was looking like…Sure wish there was a way. 

It seems like it was quite boring like right now, until the models began really teasing a bit into the month.

[High Desert Mat!]

21 minutes ago, Edmonds Husky said:

Looks like the 12z GFS caved closer to the EURO/GEM camp. Garbage model lol

Late to the party. It did that last night. 

18 for a low this morning. Coldest of the season. 

[Edmonds Husky]

Just now, High Desert Mat! said:

Late to the party. It did that last night. 

18 for a low this morning. Coldest of the season. 

I know it did, but it caved even more.

[BLI snowman]

First freeze at PDX with 31 in the early AM.

 

[GoldenEars]

There were a few splats this morning around 5-6am. Hope got lucky with some snow this morning.

[SunAndSnow]

What caused this random rainbow this morning? There was no precipitation. Ice crystals or something? 

[iFred]

3 minutes ago, SunAndSnow said:

What caused this random rainbow this morning? There was no precipitation. Ice crystals or something? 

Humidity - if you were at altitude it'd look like diamond dust floating around you.

[the_convergence_zone]

00Z EPS…

Fairly strong signal for a big AR but still 8 days out and the exact location of those can be tricky to nail.

After that, pretty much all guidance has us transitioning to cool onshore flow which will finally allow snowpack to build up. 

[Edmonds Husky]

1 minute ago, the_convergence_zone said:

00Z EPS…

Fairly strong signal for a big AR but still 8 days out and the exact location of those can be tricky to nail.

After that, pretty much all guidance has us transitioning to cool onshore flow which will finally allow snowpack to build up. 

@snow_wizard pointed out a few years ago that AR events tend to come before a cold troughy pattern which does make sense given that ARs are typically caused by a +PNA/-EPO pattern and we may transition into a -PNA pattern later

[Port Angeles Foothiller]

6 minutes ago, the_convergence_zone said:

00Z EPS…

Fairly strong signal for a big AR but still 8 days out and the exact location of those can be tricky to nail.

After that, pretty much all guidance has us transitioning to cool onshore flow which will finally allow snowpack to build up. 

Vomit.

[iFred]

[Edmonds Husky]

Just now, iFred said:

Run this with daily manifestation sessions and we might see a 08-09 or a 68-69 redux…

[Edmonds Husky]

We should have done daily manifestation sessions to have the Mariners win the ALCS…

[Port Angeles Foothiller]

Models are all garbage for their entire length, which takes us to mid December. Not helping my seasonal depression. 

[Slushy Inch]

Finally a decent Ai run

[MossMan]

3 minutes ago, Port Angeles Foothiller said:

Models are all garbage for their entire length, which takes us to mid December. Not helping my seasonal depression. 

 

2 minutes ago, Slushy Inch said:

Finally a decent Ai run

Conflicting reports! 

[Port Angeles Foothiller]

Just now, MossMan said:

 

Conflicting reports! 

Hr 342....

[ShawniganLake]

Perhaps another polar vortex disruption on the horizon. 
 

 

[MossMan]

Something big is brewing…I can taste it!

[Eugene-5SW]

12 minutes ago, Port Angeles Foothiller said:

Models are all garbage for their entire length, which takes us to mid December. Not helping my seasonal depression. 

Dude, if you can't see that the models are POISED to deliver a HAMMER BLOW of GREATNESS in Late November Early December Mid December Late December, then you're "straight up just being a wet blanket who's sole purpose is to make sure that everyone around them is miserable too."

[SeattleMarineLayerFan]

1 minute ago, Eugene-5SW said:

Dude, if you can't see that the models are POISED to deliver a HAMMER BLOW of GREATNESS in Late November Early December Mid December Late December, then you're "straight up just being a wet blanket who's sole purpose is to make sure that everyone around them is miserable too."

Late December Early January is the real deal though.

[Port Angeles Foothiller]

Just now, Eugene-5SW said:

Dude, if you can't see that the models are POISED to deliver a HAMMER BLOW of GREATNESS in Late November Early December Mid December Late December, then you're "straight up just being a wet blanket who's sole purpose is to make sure that everyone around them is miserable too."

Lmao. Perfect. I just want to not be sad. I have tried my best to avoid posting this year because usually I turn into @Edmonds Husky. Avoiding that this year and keeping my sad to myself. 

[Phishy Wx]

9 hours ago, Gradient Keeper said:

I'm trying to find a website where past computer model runs of the ECMWF and GFS are archived. I want to see what the computer models looked like December 1-4, 2008. Anyone?

Try this maybe??

 

1. Wetterzentrale (Best for Visualizing the "Run")

 

This German site has a massive archive that lets you view the initialization (analysis) and the forecast steps for historical dates.

• Website: www.wetterzentrale.de

• How to find it:

  1. Go to the menu and look for "Archive" or "Reanalysis".

  2. Select "NCEP GFS Archive" (for the American model) or "ECMWF ERA5" (for the European reanalysis).

  3. For the GFS: You can select the specific Year (2008), Month (December), and Day (1).

  4. Crucial Step: You can select the "Run" (e.g., 00Z, 06Z, 12Z, 18Z).

  5. Once the map loads, you can click the "timestep" buttons (+6, +12, +24, etc.) to see what that specific model run predicted for the future.

 

2. Meteociel (Best for Raw Data & Global Views)

 

This French site is excellent for seeing the specific 500mb patterns (the ridges and troughs) and temperature anomalies for historical dates.

• Website: www.meteociel.fr

• How to find it:

  1. Look for "Archives" in the left sidebar.

  2. Select "Archives NCEP / NOAA" (for GFS) or "Archives ERA5" (for ECMWF).

  3. Enter the date: 01-12-2008.

  4. You can toggle between "Hemisphère Nord" (Northern Hemisphere) or "USA" to get the view relevant to Spokane.

  5. Tip: Look for the "z500 + 850hPa Temp" charts to see the jet stream pattern and cold air masses.

 

 

[Port Angeles Foothiller]

The end of the AI 12z looks great. But it is hr 340+. Is it too much to ask to start seeing that play out in more models and maybe in the 200 hr range? What do I need to sacrifice? 

[Port Angeles Foothiller]

18 minutes ago, Slushy Inch said:

Finally a decent Ai run

[Edmonds Husky]

4 minutes ago, Eugene-5SW said:

Dude, if you can't see that the models are POISED to deliver a HAMMER BLOW of GREATNESS in Late November Early December Mid December Late December, then you're "straight up just being a wet blanket who's sole purpose is to make sure that everyone around them is miserable too."

It’s not to say it isn’t coming at all, it’s honestly just a “wait and see” situation. It could come in February again for all I know

[the_convergence_zone]

1 minute ago, Port Angeles Foothiller said:

The end of the AI 12z looks great. But it is hr 340+. Is it too much to ask to start seeing that play out in more models and maybe in the 200 hr range? What do I need to sacrifice? 

Probably need to wait 140 hours. And manifest. Manifest that spell. 

[Deweydog]

12 minutes ago, MossMan said:

Something big is brewing…I can taste it!

Venezuelan Vortex!

[RentonHill]

14 minutes ago, ShawniganLake said:

Perhaps another polar vortex disruption on the horizon. 
 

 

Yea, Euro last night showed something too. 

[Slushy Inch]

Euro

[Slushy Inch]

7 minutes ago, Port Angeles Foothiller said:

 

[snostorm21]

3 minutes ago, Slushy Inch said:

Euro

Looks good for mountain snow pack building.

[Slade]

10 minutes ago, Deweydog said:

Venezuelan Vortex!

Maybe thats why the airspace is closed

[Edmonds Husky]

3 minutes ago, snostorm21 said:

Looks good for mountain snow pack building.

Also a good transition to -PNA