No, this is just natural weather variability. As you can see from the post, the lowest daytime temperatures have been generally very high before this event which started mid-November.

Well, it depends on when it will occur. The record is 28-Nov-68 so we will be very close, it the forecast verifies.

It means a disruption to the usual westerly winds in the stratosphere (~30 km). Studies have shown that this disruption can spread later downwards closer to the surface, weakening westerlies and increasing the risk of cold winter weather in Europe.

Yes, the autumn-to-date has been record-warm in Fennoscandia. One week cold spell cannot be attributed to AMOC slowdown.

What do you mean by where we should be by now? Those anomalies were with respect to the 1981-2010 mean, so obviously there is warming occurred after that. Which means the warm anomalies would be weaker if using a more recent baseline.

Possibly, roughly speaking. Depends on how cold it would have been (the colder the air, the higher is the snow ratio).

But one analogy is the Merikarvia snow event in 2016. They got 73 cm of new snow with only 31.3 mm of precipitation.

During the event, the 850 hPa temperatures measured by the Tallinn radiosonde was -4.3 °C.

What if the airmass had been only a few degrees colder? Would it have been all snow?

This is a good example of these “what if” scenarios and illustrates the non-linear impacts of climate change.

Temperatures dropped almost to -30 °C last night (coldest -29.5 °C in Sodankylä Vuotso) under strong radiative inversion layer that developed on the surface.

The fresh 20–30 cm snowpack is definitely helping there to cool the surface.

The previous record was 52.8 mm in Isojoki Sarviluoma on 21.11.1971.

www.ilmatieteenlaitos.fi/sade-ennatyk...

Too bad stratobserve.com has not yet been updated for the NH winter season. I think it's one of the few online resources for monitoring strato-tropo coupling in forecasts.

Somebody needs to do that also for ECMWF model now that the data is free!