December 2014 Observations for the Pacific Northwest

[richard mann]

If the models can't figure out this weekend... the end of next week is sort of meaningless.  

 

(lol.)

[Front Ranger]

Sometimes that works better than others... this is clearly not one of those times.   When all 3 models settled on a bad solution this morning then I thought it was becoming clear.    Now as clear as mud.

 

To be fair, so did I. I gave about 2% chance of anything decent in December happening, because 98% of the time, when the models all lock in on a pattern this close, that's what ends up happening.

 

Pure insanity. Hopefully we don't all wake up tomorrow to an announcement from the NWS that global models all had a massive data error tonight.

[stuffradio]

If you look at the idea more abstractly at all, .. "this", is "it". ....

 

— As in, .. How would a support group more established, online elsewhere, be any different really. ?

 

I don't know, you're in charge of the logistics!

[TT-SEA]

FWIW... temp has gone UP here from 37 to 39 in the last hour.     For those of you tracking conditions tonight.

[richard mann]

.. Just no sense of direction.

[Kayla]

FWIW...temp dropped from 55º to 46º here in Portland in 22 minutes. Decently strong cold front. 

[richard mann]

FWIW... temp has gone UP here from 37 to 39 in the last hour.     For those of you tracking conditions tonight.

 

In which room of your house—are you talking about more specifically here. ? 

[Front Ranger]

Did Jim write this song for Tim???

 

https://www.youtube.com/watch?v=CRtJo_7TfjE

 

I listened to that for about 45 seconds and then had to stop it before my ears shut down.

[Snow]

[luvssnow_spokane]

FWIW my temp has gone from 53 to 41 since about 5pm today... Raining. Anyone jealous? 

[Front Ranger]

FWIW... temp has gone UP here from 37 to 39 in the last hour.     For those of you tracking conditions tonight.

 

SEA has been steadily dropping, down to 41/37 now. NWS wasn't expecting possible snow mixing until 3-4 am anyway.

[Gradient Keeper]

00z Review
Thoughts: Who the hell knows anymore. We've seen crazy model swings many times before, flip/flops from run to run, but 12z to 00z today may take the cake(If the fat kid who loves cake hadn't already), but seriously, The differences on the 12z ECMWF/GFS to 00z is astounding, if not absurdly so. We have amazing potential for a prolonged arctic blast, and yet at the same time it could completely flop the other way becoming progressive again. It's encouraging that the GFS Ensembles have improved. I am eager to know how ECMWF Ensembles look tonight. Onto 6z/12z(especially) tomorrow

[snow_wizard]

If the ECMWF were to verify verbatim we would be talking about a pretty dramatic enhanced inversion. Perfect surface pressure gradients to maintain cold once the legitimate cold moves away at the mid and upper levels. This first round of cold could easily end up being the appetizer though.

[Gradient Keeper]

[Model Countdown]
Up next....
6z NAM 30 minutes
6z GFS 2 hours 10 minutes
-----------------------------------
12z NAM 6 hours 30 minutes
12z GFS 8 hours 10 minutes
12z GEM 9 hours 30 minutes
12z ECMWF 10 hours 40 minutes

[snow_wizard]

A number of cold members on tonight's ensemble after the retrogression during week two. Some look really snowy too. No doubt there is a very obvious retrogression trend showing up on tonight's run. Could be a solid two to three weeks of cold weather coming up.

[snow_wizard]

FWIW my temp has gone from 53 to 41 since about 5pm today... Raining. Anyone jealous?

You could easily see it go to snow by morning.

[BLI snowman]

If the ECMWF were to verify verbatim we would be talking about a pretty dramatic enhanced inversion. Perfect surface pressure gradients to maintain cold once the legitimate cold moves away at the mid and upper levels. This first round of cold could easily end up being the appetizer though.

 

Sounds familiar! #drycold

[Gradient Keeper]

00z GFS Ensembles 850mb temp mean ...

Dramatic improvement before day 10....

 

Portland

 

Seattle

 

Vancouver, BC

[TT-SEA]

A number of cold members on tonight's ensemble after the retrogression during week two. Some look really snowy too. No doubt there is a very obvious retrogression trend showing up on tonight's run. Could be a solid two to three weeks of cold weather coming up.

There is nothing but doubt right now. No doubt about it!

[snow_wizard]

Pretty stunning how may really cold ensembles there are for the cold snap early next week.  This still has potential to go further than tonight's runs indicated.  Pretty easy to see where cold snap number 2 could emerge also.

 

[Snow]

[snow_wizard]

Sounds familiar! #drycold

 

That has to end at some point.

[snow_wizard]

The new 00z UKMET looks great!

 

 

Wowzers!  That is purdy!

[TT-SEA]

My temp has stabilized between 38 and 39.

 

This event had become a prolific rain producer here... almost 2 inches for the day,.

[snow_wizard]

The thing I like about all of these solutions is a lot of surface high pressure remains over the ocean which means the offshore flow will kept much weaker.  For most areas that will mean better decoupling. 

[richard mann]

There is nothing but doubt right now. No doubt about it!

 

Another strong statement here too, Tim.

 

(.. Strong, comedically.)

[Snow]

Wowzers! That is purdy!

Yup, 2nd best model in the world is on board!

[Gradient Keeper]

Wowzers!  That is purdy!

Major blast from the northeast

 

Another fantastic run from the UK Folks model....

Should point out this model has been insistent on an arctic blast after HR 96-120.

 

Disclaimer: Don't pee your pants

[richard mann]

I always knew things would be just like this. (honk. honk.)

 

— What's that "Kentucky Derby" "home-stretch", thing again. ..... ?

[Snow]

[Gradient Keeper]

Okay, going to watch TV, relax... I might in fact go to sleep early who knows....

 

Peace

[luvssnow_spokane]

FWIW.. It is 38 degrees here at 500 ft with mixed snow and rain. I am out to pick my wife up from her shift at target and the snow and rain is a 50% mix.

[MossMan]

Starting to have some slush mixing in at my place! And wow what a difference in model runs today, crazy stuff! Guess we will see what roller coaster we will have tomorrow with the Christmas Eve 12z's!

[richard mann]

-
More real time, with some amount of extrapolation. (General speculation.)
 
http://www.ghcc.msfc.nasa.gov/GOES/globalir.html. — Dial up the 30 frame animation potential here. Or check whatever other general resource covering the same idea, however. 

http://www.fvalk.com/images/Day image/GOES-10-0000.jpg .0300z,-0600z,-0900z,-1200z,-1500z,-1800z,-2100z .@
http://weather.unisys.com/upper air/ua hem.php?plot=n5&inv=0&t=cur
http://www.atmos.washington.edu/~ovens/loops/
 
•  Main ridging having developed over the past few days—with colder air's both at the same time having been in general recession for the past few days, while also having been slowing its over-all pace and progress more eastward, …
 
… being punched through, with a lesser far south-reaching trough of cold air's current more direct south leaning direction (trajectory).
 
•  Along together with otherwise, stronger cold east of the Rockies, still having been allowed more significant access south, and with its spread and movement more directly south, working to "block" the progress of the greater flow (train.) of elements below colder and warmer either side of the Jet north and south, eastward.
 
— That train and flow set to slow steadily, daily progressively more, over the next few to several days. Cold perhaps, able to stay within the main more northern tier of the mid-latitudes, where looked at more latitudinally. -http://www.proxigee.com/twitter_logo-t12.png

[epiceast]

The GEM having 3 ridgy runs in a row should tell you something about the chances of this event going cold.. Even if it does go cold there is no snow potential except for tonight, so nothing to get excited over.

[snow_wizard]

The GEM having 3 ridgy runs in a row should tell you something about the chances of this event going cold.. Even if it does go cold there is no snow potential except for tonight, so nothing to get excited over.

You should know that Arctic air always brings unforeseen possibilities for snow. I don't think the GEM having such crappy runs means a whole lot right now.  There is also the retrogression potential later on.

 

Besides...it's a whole lot better than the warm rain we've been seeing.

[snow_wizard]

FWIW.. It is 38 degrees here at 500 ft with mixed snow and rain. I am out to pick my wife up from her shift at target and the snow and rain is a 50% mix.

That is great news. You're only a tad higher than I am. Still looks like a lot of heavy precip yet to come tonight.

[bainbridgekid]

 

Pretty stunning how may really cold ensembles there are for the cold snap early next week.  This still has potential to go further than tonight's runs indicated.  Pretty easy to see where cold snap number 2 could emerge also.

 

http://www.wetterzentrale.de/pics/MT8_Seattle_USA_ens.png

 

Absolutely laughable how much colder the 00z Ensembles are for the weekend and early next week than the 18z ones were. Biggest swing inside 7 days I have ever seen.

 

[Snow]

[Front Ranger]

What's interesting is that all models are showing a tanked EPO, but the colder models are no longer advertising -AO. This goes to show that the most important driver for significant Arctic air into the CONUS is a -EPO blocking ridge. -AO, or an Arctic block, can help dislodge some of the coldest air, but a -EPO is usually essential in directing it towards us.