Age: Timeless.
Appearance(s): Manchester, Sheffield, Edinburgh and Glasgow; perhaps even coming to your town soon.
On tour, are they? Who?
This band, Thundersnow. Any good? It's not a band, it's a weather phenomenon that has been occurring recently across Britain.
What is it? It's thunder that happens during a snowstorm, hence "thundersnow".
Wouldn't it be more accurate to call it "snowthunder"? There's also lightning, and sometimes hail, and sometimes graupel.
Graupel? What's graupel? A sort of frozen pellet, formed when snow flakes are impregnated with super-cooled water droplets under particular atmospheric conditions, and sometimes referred to as soft hail.
I don't mind learning something new every day, but I draw the line at learning two things. Let's stick with thundersnow – what causes it? In this case it's cold air passing over a warm sea, a circumstance akin to the "lake-effect" blizzards that brew up over the American north-east.
So it's quite common? Not at all. Elevated convection – moist air rising into the troposphere to produce thunderstorms – rarely happens at temperatures that would support snowfall. There are on average just 6.3 recorded thundersnow events a year across the whole of the US. It's rarer still in the UK.
That would explain why I've never heard of it. Or heard it – the snow tends to muffle the sound of the thunder, so it's really only audible within a two- to three-mile radius.
What else do you get with thundersnow? Typically, high winds and rapid accumulation – between two and four inches an hour, or more.
How long must I wait before I get a chance to witness this freaky phenomenon? You might get lucky again today, but it's probably a once in a lifetime thing. You just have to be in the right place at the right time.
Or, failing that, Sheffield. Be nice. My mum's from Sheffield.
Do say: "OMG I just saw #thundersnow in Glasgow!!! It was AWESOME."
Don't say: "I saw #thundersnow supporting Deacon Blue in Glasgow in 89. They were rubbish."
