Possible Arctic outbreak -- early December 2013

[Tim Vasquez]

It does look more certain that we'll be seeing some sort of cold wave later next week. An area of lift spreading into the Alaskan interior will be laying down quite a bit of fresh snow cover around midweek, and depending on the clearing we may see substantial radiational cooling and probably the production of a large arctic air mass. The GFS builds a large *1060 mb high* over northwest Canada towards the 240 hour panels, and so does the ECMWF. Given that there are consistent signals of troughiness ahead of the upper ridge, this already looks to be more of a cloudy/snowy arctic outbreak than a dry & fair one. And really that's about all that can be said at this point.

It's pointless to do much speculation right now, but it will be something to keep an eye on once we get past the holidays.

 

[Karen St John]

I can almost see the pink line in the sky from my house.

 

[Marcus Diaz]

Well this appears to be coming to fruition. High temps in Amarillo will be mid teens to low 20s on Thursday-Saturday. Couple of inches of snow expected also. But damn, I hate when it gets THAT cold.

 

[Tim Vasquez]

Looks like this could be a rather prolonged Arctic outbreak too.... the polar jet is showing a very long fetch of upper-level flow coming off the icepack north of Alaska straight south into North America. The western stream out of the Pacific also intensifies, so I don't think we're going to be out of the woods for over a week here in the central and southern Plains. If any significant snow cover gets established we could see temperatures going even lower than forecast.

 

[Stephen Levine]

Interestingly and unusually, there is an ice storm warning around Fairbanks AK, along with unusually mild weather across the state.
In fact, a period of freezing rain is predicted all the way to the far north coast!

 

[Matt Ashworth]

Well a few days ago Colorado got hammered by some snow and sub-0 temperatures. Here in Longmont at least the roads all froze over and everything's been a mess. Things aren't supposed to 'warm up' until next week when the high reaches above 30...I hate this kind of weather. It does remind me of the few winters I recently spent in nearby Greeley where the average morning temperature was in the neighborhood of -40 for a few days.

 

[Tim Vasquez]

Well, here is a limiting factor as to how cold it will get. Kansas and areas north missed out on the snow, so that doesn't paint a good picture for regeneration of the polar air. This air mass is extremely cold for this time of year, but what we have is being modified pretty quickly.

We did get about 3 inches of snow at my place. About to go out and test whether I'm able to drive on it. I'm not getting my hopes up, though... I have a Ford F150 and it seems to perform poorly on snow.

 

[KenMcWatters]

Here is a pic from my backyard in Broken Arrow OK - I measured close to 4" but media reports say 5 to 5.5 inches were recorded here in the Tulsa metro.



The roads are snowpacked as seen here, and hard to get traction but driveable.