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Thundersnow: what causes it? Thundersnow: what causes it?
(2 months later)
Age: Timeless.Age: Timeless.
Appearance(s): Manchester, Sheffield, Edinburgh and Glasgow; perhaps even coming to your town soon.Appearance(s): Manchester, Sheffield, Edinburgh and Glasgow; perhaps even coming to your town soon.
On tour, are they? Who?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.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".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.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.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.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.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.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.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.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.Or, failing that, Sheffield. Be nice. My mum's from Sheffield.
Do say: "OMG I just saw #thundersnow in Glasgow!!! It was AWESOME."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."Don't say: "I saw #thundersnow supporting Deacon Blue in Glasgow in 89. They were rubbish."
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