The Queensferry Crossing has closed to all traffic after parts of the country endured 'thundersnow' overnight and awoke to wintry conditions on the roads.

BEAR Scotland said the bridge has been forced to close due to the ongoing weather conditions, including falling ice and snow.

All traffic is being diverted via the A985 Kincardine Bridge.

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Chris Tracey, BEAR Scotland’s South East Unit Bridges Manager, said: “The safety of bridge users comes first and therefore we’ve made the decision to temporarily close the Queensferry Crossing due to ongoing adverse weather conditions.

“We are constantly monitoring the structure in real time using a bespoke system of weather sensors on the towers and deck of the Queensferry Crossing.

“We apologise for any inconvenience caused to road users by this closure and will reopen the bridge when safe to do so.”

The Met Office has issued yellow warnings of snow for much of the country, which are valid until 9am on Friday.

It states: “The bulk of snow accumulations will be over hills and mountains. 2-5cm of snow is possible above 150m, with transient sleet/snow at lower elevations.

“Steadily increasing amounts are likely at higher levels; perhaps as much as 10-20cm above 400m, significantly affecting higher transport routes for a time before it turns to rain.”

Elsewhere in Scotland, ScotRail has warned of "significant disruption" on multiple routes due to the heavy snow, with Traffic Scotland urging motorists to take care and check their routes for travelling. 

Police in Ayrshire tweeted that many roads in the area are affected by snow and urged people to take extra care.

Elsewhere, Police Scotland reported that the A70 Lanark Road West, just after Belerno, is closed due to an articulated lorry stuck due to weather.

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Meanwhile, many Scots were rudely awoken from their slumber due to a phenomenon known as 'thundersnow', which was heard across Edinburgh and the Lothians last night.

Some people even contacted police to raise concerns after they heard the strange noises amid stormy weather.

Police Scotland Control Rooms tweeted at around 5am on Friday: “We have received a number of calls regarding people concerned about explosions heard.

“Please do not be alarmed, we are currently experiencing thunder and lightning.”

Many people took to social media to describe the noises they heard.

Edinpotter63 tweeted: “Good morning from snowy Edinburgh. Woken up at 4.40 by thundersnow!”, while Dr Bryony Coombs @BryonyCoombs tweeted: “Good morning to everyone in #Edinburgh who woke in the middle of the night to huge crashes of thunder, lightning and snow… #thundersnow.”

Em Dee captured some incredible scenes of thundersnow as it struck Penicuik in Midlothian, near Edinbugh.

She said she woke up with "quite a shock".

What is thundersnow?

According to the Met Office, when thunderstorms form in wintry conditions they can sometimes give rise to heavy downpours of snow, and this, along with the usual thunder and lightning, is called 'thundersnow'.

Thundersnow is unusual only because it can only occur in a few months of the year.

"When thundersnow occurs at night the lightning appears brighter - this is because the light reflects off the snowflakes", the Met Office writes on its website.

"Interestingly, the snow contained within the thunderstorm acts to dampen the sound of the thunder.

"While the thunder from a typical thunderstorm might be heard many miles away, the thunder during a thundersnow event will only be heard if you are within 2 to 3 miles of the lightning."