SCOTLAND is facing a severe cold snap which could last for three weeks and bring widespread snow, ice and travel chaos as rare weather conditions sweep down from the Arctic north.

Forecasters say temperatures could even drop as low as -18C should the bad spell of weather hit later this month.

Met Office officials briefed the Cabinet Office, transport bosses, councils and emergency services on the possibility of a phenomenon known as a “Sudden Stratospheric Warming” (SSW) occurring, which sees the North Pole’s high-altitude air heat up and shunt cold low-level Arctic air south to Scotland.

The weather pattern, said to be behind the big freeze of 2010, is thought to be taking place this year and usually brings ice and snow to Scotland, with the bad weather arriving from the east.

The Met Office’s February to April forecast predicted “colder and drier conditions” from the end of this week, sparking a cold snap likely to last for around three weeks and possibly into the middle of March.

The briefing continued: “The probability of Sudden Stratospheric Warming is higher than normal in February.

“These events disrupt the stratospheric polar vortex and, more often than not, bring cold weather to the UK.”

Yellow 'be aware' warnings for ice and strong winds have already been issued for Strathclyde, Highlands and the Western Isles, Grampian, Central, Tayside & Fife, and Dumfries, Galloway, Lothian & Borders.

The high winds warning is in place from 11am until 10pm tonight, while the ice alert is valid from 8pm until 10am tomorrow morning. Snow is also forecast in the southern and eastern Highlands.

The last SSW event to hit Scotland was in early 2013, which saw the coldest March for 51 years, with snow and -12.5C lows as late as March 31 in Braemar, Aberdeenshire.

Similar conditions also triggered -16.1C lows in Altnaharra, in the Highlands, in November 2010, starting December 2010’s month-long Big Freeze, while -18.4C lows were felt in the Highlands in February 2009.

The Met Office’s Professor Adam Scaife said: “A Sudden Stratospheric Warming involves a complete reversal of the high altitude polar jet stream. This can burrow into the lower stratosphere.The Atlantic jet stream often weakens and moves south. This allows cold air from the east into northern Europe and the UK.”

A Met Office forecaster added: “It is likely to become rather cold in the east, and from mid-February until the beginning of March, high pressure over the continent will gradually build.

“Our weather is likely to stay on the cold side, with a lot of dry days. Nights will bring further frost. The start of March may turn more unsettled.”

The warning comes after two avalanches hit Scotland’s mountains at the weekend.

In the first incident, three climbers were injured on Ben Nevis at about 12.15pm on Saturday.

Coastguard helicopters and Lochaber Mountain Rescue Team were involved in the operation to rescue the climbers.

Another climber was airlifted to hospital after being injured in an avalanche in the Cairngorms on Saturday afternoon.

The man injured his leg while climbing in Garbh Choire, Braeriach.

Braemar Mountain Rescue team warned that “full on winter conditions” had returned to Scotland’s mountains.