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The January records for Prague are 17C and –27C, so the record high is the same as for London. Generally, as you head east, the record highs stay the same in the high teens to low twenties and the record lows go down into the minus twenties and thirties, partly due to the greater continental variability of the climate, and partly due to the Föhn effect of the Alps and the Carpathians. If you take Salzburg in Austria, the January records are +21C and –30C. In Nowy Targ in the foothills of the Polish mountains, for example, the record high and low is 16C and –37C. Krakow is 17C and –30C. Once you go east of Poland, or north, away from high ground, the record highs begin to come down too, so in the Ukraine, Kiev has record January highs and lows of 11C and –32C respectively, and north, away from the mountains, Warsaw has records of 13C and –31C.

Keep in mind that above average at UK latitudes in central Canada means about minus 20 degrees instead of the usual minus 30. Even in tropical Ottawa, where it's warming up from -22 to +7, I reckon there'll be snow on the ground. It is good to see Europe closer to average with the GFS showing a significant drop in temperatures over the continent. That probably won't affect us, but it *can*, and that's a start.

I thought someone would have fixed this ages ago, but for months now, you have had a glaring spelling mistake in the title on the Netweather Commercial site. It says ‘Netweather Commmercial’ with three ‘m’s and not two. https://www.netweather.tv/commercial Honestly, this huge error's been there for yonks and I've no idea why nobody's picked up on it.

I remember cycling to work when we got the dusting in London in late October 2008. I wonder what sort of uppers we had back then. Regardless, we've got Tropical Storm Lorenzo to get through first, and my garden's already sodden.

I haven't seen the reanalysis, but is it really record-breaking? There was 5 cm of snow on 12 Oct 2015 in Krakow, (following 35C heat in September and average daytime August highs a shade under 30C.) And I was 70 miles north of Krakow in the snowstorm of Oct 2012 when for three days it failed to rise above freezing. The continent can get very cold, very quick. And yet it'll still rain on Christmas.

Jon, if those uppers around the 15 degree mark were to come off, then provided we have dry weather and clear skies, we could be edging towards 30C at ground level, autumn equinox be damned. Those uppers have produced high 20s in October after all.

Honestly, in spite of the trough, the weather in Central Europe looks only marginally less good than our own. If anything, the single digit 850s seem to produce moderate surface temperatures more likely to be enjoyed than endured. The first part of July is modelled to be pretty nice everywhere, from the Med up to Scandinavia, except maybe Iceland. Long may it continue.

LOL. Brilliant. I meant the "wrong type of snow" from our perspective, i.e. the kind that fails to accumulate, except maybe on car windscreens. Nothing more irritating than getting a full day of heavy, falling snow for there to be nothing on the ground at the end of it.

I'd appreciate 850s at or below minus 10C, for one. Sleety slush, cold rain and "the wrong type of snow" are very much a risk on lower ground.

Minus 40 degree 850 hPa temperatures forecast for Minnesota and Wisconsin, minus 30s across a wide swathe of the Midwest. This is an extreme cold event. I've not seen 850s like this outside of northeastern Siberia in a long time. At times throughout the run you see negative 30s dipping south of the 40th parallel. That's like southern Spain or Italy.

The sun's not strong. We're just in a bad position geographically. Chicago, which is 600 miles south of the south coast of England is forecast a daytime high around minus 20C next week. Winnipeg, which is south of London is expecting sunny skies and minus 32C for a maximum temperature around the same time. The sun is well and truly powerless against negative double digit 850s at our latitude, and will be until late March. The lacklustre 850s in the chart below could throw a few surprises with heavy enough precipitation. I wouldn't rule it out. It's marginal, yes, but 9 out of 10 UK snowfalls are.

Awesome

Well done for getting that shot of thundersnow. Great stream of snow showers from Teesside to Darlo in the last hour or so. Hoping it resumes and continues overnight.

Notable now is the absence of any sort of strong Siberian High. In the 1986 chart you posted, we had a 1050mb Siberian High centred over Mongolia that later retrogressed to Scandinavia. The Siberian High is very weak this year and that is unlikely to change in the next 10 days or so. It therefore looks unlikely that we get a surprise attack from the East in the next week or so.

Amazing cold plunge. Dalhart, TX, 10th at 1pm: +29C (high) and at midnight -3C (low) Dalhart, TX, 12th at 4pm: -7C (high). Denver, CO, 9th at 4pm: +21C (high) Denver, CO, 12th at 3pm: -14C (high) and at midnight -25C (low) Casper, WY, 8th at 3pm: +18C (high) Casper, WY, 12th at 3pm: -16C (high) and at midnight -33C (low).

I guess if the NAO turns negative, both Eastern N. America and Western Europe get affected. The means for the Northeast and Midwest are about -10C to 0C whereas for Northwestern Europe they're about 0C to 5C, so it often takes longer for Western Europe to experience wintry weather from a negative NAO than it does for the eastern States, which are generally quite cold to begin with anyway. In that sense, wintry weather in the US resulting from Atlantic blocking often precedes that in Western Europe. This particular North American cold/snow outbreak is not related to a negative NAO, however, so Western Europe need not expect extreme cold any time soon. That said, anything can happen, but if it does, it probably won't be related to the recent American coldwave in any obvious way.

When I look at the charts, I often see extreme cold from Canada getting up to the middle of the Atlantic up to about 30W as 850mb temps of -10 or -15C, and even sometimes reaching Ireland as -5C at 850mb. All we need to do is halve the size of the second largest ocean on the planet, and then even our zonal weather will be snowy a lot of the time, without ever getting too cold. Seemples, lol.

I mean, essentially what they're getting is blocking to their west, giving them a northerly stretching all the way up to the North Pole. The Arctic Ocean is frozen on the American side, so it begins to act almost like a continent in itself, and if anything, the air gets colder as it heads south over the higher latitudes of the true continent until it reaches far south enough for the sun angle to begin to warm it up. By that time, the air is so cold, you can occasionally get -30 degree lows at latitudes equivalent to those of North Africa.We don't have a nearby source region of cold air. To our NE, the European Arctic remains unfrozen all year, even European Russia is exceedingly mild for its latitude, and Siberia is far too far to our east and partially blocked by the Ural mountains. The truly cold air has a hard time reaching Eastern Europe and has typically already been modified significantly by the time it reaches Western Russia. Then it has to travel thousands of miles more over the upper middle latitudes to reach us, getting modified by the sun, the Baltic, the North Sea, the Mediterranean and even the relatively mild Western European continent itself. So on top of the island effect, we don't even have a very continental continent to our east. No pressure alignment, no matter how extreme, can get air nearly as cold as what is possible a thousands miles to our south on the other side of the Atlantic. Eastern Europe and parts of Scandinavia, despite generally being quite mild (from a global perspective), do occasionally reach the -30s, and some of our coldest weather ever has been from that continental air making its way west. That said, it's fairly difficult to establish continental air over Eastern Europe, let alone to get it to retrogress west. The odds are stacked against us whichever way you look at it. On the bright side, our northerly latitude means we can get modestly cold air coming in quite easily and even an oceanic northerly can be cold enough to produce snow at lower levels.

Yes, but low pressure systems in eastern North America tend to bring rather different airmasses. We have endless ocean to the north and west whereas they have a continent stretching up into the Arctic, so even a mild zonality there typically sees temperatures in the negative double digits for our latitude. It is far, far, far easier for places south of 40 degrees N to get severe winter weather there than it is for us to get it even in Scotland, north of 55 degrees N. The PV doesn't help us much at all.