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@raz.org.rain Lytton, British Columbia, at 50°N, same latitude as the south coast of England, hit 49.6°C recently. Exceeding the 40°C record in the UK is definitely possible.

Yes, the differences between the seasons in terms of how they look are very dramatic. I've always used the car, but I've been thinking of doing one of the train journeys – Glacier/Bernina Express – too. How did you find it? Happy Christmas to you too.

Around minus 12 degrees, late this morning on the shore of the now almost completely frozen Lake St Moritz. 20221217.mp4

Lake Sils. Temperature at nearby Samedan Airport. Min: –26°C Max: –10°C petal_20221212_164914.mp4

I understand. At the moment, and probably for at least the next year, neither do I. Electric blankets are great for cosifying a cold room.

17°C to 30°C rollercoaster. I'm on a tariff where I have (nearly) free electricity all day on Sundays and holidays and from 11pm to 7am on weekdays, so I set the AC to 30°C and put on as many convectors on as possible without blowing out the fuses to heat the house as much as I can (except the bedroom) overnight. In practice, the house gets up to about 26°C by the morning, and then drops to about 23°C by 9am. The sunshine heats the living room during the day, but in late afternoon, once the temperature in the living room drops below 21°C, I might put some electric heating blankets on. If the temperature drops below 19°C in the evening, I'll use 0.5 kWh of expensive peak time electricity to pep the living room up again with half an hour of AC blasting out hot air. The kitchens/bedrooms might drop to 17°C before the heating comes on again at 11pm.

Oh Lord. I'd get air-to-air heat pumps installed in every room. Costs £1000-£1500 per room for device and installation, and uses about ⅓ the power of an electric heater for the same heat output, which means it costs about the same as gas to operate, but without the faff and expense of installing a whole new central heating system.

Forced air systems used boilers (or furnaces, as they are known in North America) that could heat the air only, which meant you needed a separate system to heat your hot water. I don't know if this is still true. Some people also prefer the fairly quiet operation and radiant heat from radiators. Furthermore, central AC hasn't really taken off in the UK.

As far as I'm aware, it's six and two threes, i.e. not much difference, though the fact it gets up to temperature more quickly might be an advantage if you're out of the house a lot throughout the day. Its original advantage in the past was that you could use the same system for heating and cooling, though these days, there is more flexibility with heating/cooling options.

Forced air is basically where a room is heated through air ducts instead of water-filled radiators. Think hotels/some office buildings. It's popular in North America because most of the continent is subject to both extreme heat and extreme cold, and you can use the air ducts to deliver cold, air-conditioned air. It's become the standard even in places that don't need AC. Outside of North America, most homes don't have air ducts, but these days you can achieve the same effect with ductless mini-split AC.

Interesting. I have both traditional gas/radiator heating and several mini-split AC units. The AC definitely gets things up to temperature very quickly, which means I can afford to let things get colder when I'm out. Given the COP ≈ 4, it saves a fair amount over using the gas central heating, since I don't need to use it as much or heat the whole house all of the time.

Yep, even here. It refused to get below the low 20s C until November, but it's definitely cooled off a fair bit in the last month.

First snow at low levels here in northern Italy. Video below. And, case in point, temperature is a mild 0°C all the way from ~1750 metres down to as close to see level as you can get (around 300 metres). Video: VID_20221209_142908.mp4

True. Prolonged periods of temperatures near or below zero as forecast may spell trouble for scarce gas reserves and tight electric generation capacity, especially if coupled with a cold, gloomy, windless spell, if after any snow the high settles over the north of the UK.

Loads of reasons. Yes, the Alps do block the cold air from the North, but they also block some of the mild air from the West, and the Appenines block some of the mild air from the Med. Compare Turin (January mean 1°C) to Genoa (January mean 9°C). They're only 2 hours apart, but the Appenine mountains prevent the mild Mediterranean air from reaching Turin. In fact, Northern Italy is more or less the least windy region in Europe (see attached map), giving time for home-grown cold to develop. Furthermore, the nearby mountains also block much of the clouds stuck over Europe in winter, meaning that nights are typically clear, allowing nighttime temperatures to drop further. At the same time, the Po Valley is prone to fogs that struggle to lift, thus depressing daytime highs. In addition, even though 45°N is far south of the UK, it's far north by global standards. While you seldom get uppers much below –5°C, as they are blocked by the mountains, the latitude is still high enough to allow a shallow layer of cold air to develop in the windless air at the surface in spite of the mild uppers. As a result of the cold surface layer, the average January temperature in Turin is about the same as it is in the nearby mountains at an elevation of around 1700 metres. In Turin (elev. 275 metres), the January average is 1°C – colder than almost anywhere in Scotland. Reference: https://it.m.wikipedia.org/wiki/Stazione_meteorologica_di_Torino_Centro On Monte Malanotte (elev. 1750 metres), the January mean is almost the same at 0°C – incredibly mild for that altitude, and, globally, fairly mild for the latitude too. Reference: https://it.m.wikipedia.org/wiki/Stazione_meteorologica_di_Monte_Malanotte Obviously, there will be mountain valleys much colder than that. You only need to look not too far away in my neck of the woods at St Moritz (1800 metres), whose average morning lows below –15°C make Moscow seem mild in comparison. In fact, Samedan, a few miles away, has an average low of –17°C, easily reaching –30°C every few years. But again, even that cold is locally-grown, since the upper air temperatures coming in from the Atlantic ocean aren't particularly cold at all – typically around 0°C at 850 hPa, and even rare blasts of continental cold can't penetrate the crest of the Alps unmodified. So, lack of wind, lower humidity, clear skies, radiation fog and the (still) fairly high latitude all contribute to giving the climate a semi-continental flavour. The windlessness, especially, gives the air several days' time to cool off during the long nights before it blows away, meaning homegrown shallow cold develops readily, making the climate far more continental than you would expect.