Coldest May night in five years — −6.1°C at Altnaharra, snow in Shetland

[HighlandHouseEdge]

Bit of Scottish weather weirdness worth flagging. The Met Office recorded −6.1°C overnight at Altnaharra in Sutherland on Wednesday into Thursday, the coldest May night anywhere in the UK in five years. Kinbrace −5.3°C, Braemar −4.3°C, Dyce in Aberdeen still hitting −1.1°C. Shetland had actual snow showers on Wednesday morning before warming up.

BBC and PA were running it through the day — the AOL/PA piece I read this morning had a good summary. Low pressure parked north of Shetland dragged Arctic air south, then it cleared overnight and we got the long radiation cooling. Classic spring inversion conditions: clear sky, no wind, snow on the high ground still, temperatures fall through the floor.

The interesting bit is the comparison: this is the coldest May UK low since 2021. May frosts in the Highlands are not unusual but anywhere near minus six in the third week is. For anyone with a garden, the supermarket bedding plants that went in on the bank holiday weekend will be looking sad this morning. I've lost two tomato plants and a basil already and I'm in Inverness.

Full coverage on aol.com with the PA wire piece. Decent slot of weather geek facts in there if you like that kind of thing.

[NewbiePunterNeil]

Falkirk had a hard frost on Thursday morning too, ice on the windscreen properly thick. Lost a row of courgettes to it. My neighbour swears she planted hers out three weeks ago which is, with respect, always optimistic in central Scotland regardless of the long-range forecast.

The Shetland snow pictures on BBC Scotland looked surreal — May, lambs in the field, snow on the ground.

[WeeWinsMorag]

Stirling Castle had frost on the cobbles when I walked past on Thursday morning. Tourists in shorts with cameras out, locals in actual coats. The two-Scotlands look.

Don't buy bedding plants from the supermarkets in May. Folk wisdom. The garden centres won't even put theirs out until end of May for a reason.

[FionaSlotsFan]

Met Office Twitter feed was busy with it. The Altnaharra figure is an outlier station — bowl-shape valley, classic cold-air drainage location, it routinely runs four or five degrees colder than surrounding stations on calm clear nights. Still genuinely the coldest May UK low since 2021 though, the league-table position is real.

Bands of warmer air from the Atlantic pushing in for the weekend per the regional forecast. Tomato plants might survive after all.

[Scottish Skeptic99]

The Altnaharra reading gets wheeled out every time we have a cold snap but FionaSlotsFan is spot-on about the topography. That station sits in what's essentially a frost pocket — cold air settles there like water in a bathtub on clear nights. The surrounding area probably ran closer to -2°C or -3°C, which is still proper cold for May but not the dramatic headline figure.

What's more telling is the pattern across multiple stations hitting similar lows simultaneously. When you see Braemar, Tulloch Bridge, and even lower elevation spots like Kinloss all dropping below freezing on the same night, that's a genuine cold air mass, not just local geography doing its usual tricks.

[inverness_ian]

That -2°C to -3°C range you mention for the surrounding area matches what I've seen up here over the decades. Altnaharra's been the go-to dramatic headline station since the 1980s — same frost hollow effect, same reliable sub-zero readings when the rest of the Highlands are just kissing freezing.

What caught my eye this time was the Shetland snow mention in the thread title. May snow that far north isn't unheard of but it's worth noting — I've tracked weather patterns for forty-odd years and the combination of mainland frost pockets hitting -6°C while Shetland gets actual accumulation suggests a proper Arctic air mass, not just local radiative cooling.