not just 65N, mid-latitudes are where it is most prominent, probs 40-65N or so...
(pictures snipped for space)
So compared to the arctic-based cci-reanalyzer graphs we're used to (plenty posted upthread), you're showing me a very different image. Just north of Kazakhstan/Russian border sits a 10C+ blob of warmth, where today's 'nowcast' shows -20C anomaly. That's a huge swing and makes these hard to compare. Granted you've picked a 9-day-in-the-future forecast, but I don't think we'll see a flip like that.
Your graph of snowfall anomaly is hard to compare because it doesn't show the coverage anomaly. Snowfall has been very heavy in Greenland this year (just look at DMI surface mass budgets) but that does little for Albedo. Also, It's currently 16 C in Shanghai with 20s forecast later in the week. It doesn't look like "almost snowing" weather to me.
Granted - Rutgers does show a lot of positive snow cover anomaly as such. I'm willing to accept it as a real thing.
So is there enough light? Messing with a calculator -
75 N - always night (0 W/m^2)
65 N - 26 W/m^2 average today, dropping to 10 W/m^2 by the end of the month
55 N - 89 W/m^2 average, dropping to 65 W/m^2
45 N - 159 W/m^2 average, dropping to 133 W/m^2
and Shanghai? 33N - 262 -> 232
The core of the cold anomaly (as seen on CCI-reanalyzer's GFS-generated anomaly plot) I'd put somewhere near Tomsk, so (say) 56N. It's about 1/6th the peak of the summer.
Sadly I don't have time to calculate the snow coverage anomaly at those latitudes, compare with albedo numbers, and put an actual number on it, but we could do all those things.
Except... I notice that the snow cover anomaly covers all of Canada, where it's been warm, too. It makes it a much more difficult argument given that.