Devon and Cornwall braced for cold snap
Miles Davis/BBCPeople in Devon and Cornwall are preparing for extremely cold weather in the coming days.
Temperatures are expected to drop as low as -5C (23F) at night and there is the possibility of snow on the moors.
The Met Office has issued a yellow warning for ice in parts of the South West from 17:00 GMT on Wednesday until 18:00 on Thursday.
The UK Health Security Agency has issued a cold weather alert for all of England.
Local authorities will be gritting roads and helping homeless people to find somewhere warm to sleep.
The level three cold weather alert was triggered by the Exeter-based Met Office.
It said there was "a 90% probability of severe cold weather and icy conditions" from 18:00 on Wednesday which could last until Monday.
Analysis
by David Braine, BBC senior weather forecaster
Cold weather in December is not unusual, but after an unusually mild autumn it is a bit of a shock to find such low temperatures so early in the winter.
Last December [2021] was particularly mild, especially at night, with very little frost and after Christmas temperatures at Exeter Airport at night were no lower than 14C.
This December is different, the blocked pattern that gave us the hot dry weather over the summer is effectively still with us, it was responsible for the very wet weather we had in November.
This wet weather might have continued into December but subtle changes in the jet stream and the overall weather pattern across the northern hemisphere means the pattern has moved to bring Arctic air over the UK from the north and north east.
This will bring below average temperatures, during the day maybe 4-6C (39-3F) but more apparent at night with the potential for the next three nights of temperatures as low as -5C (23F).
It also tends to bring dry air so limited rainfall if at all, but also the risk of wintry showers especially over the moors.
A prolonged cold spell has big impacts on our NHS, social care, infrastructure, and road and rail networks, hence the severe cold weather alert level three from the Met Office in conjunction with the UK Health Security Agency.
The cold weather alert requires social and healthcare services to "target specific actions" to help high-risk groups.
Cornwall has activated its severe weather protocol designed to help all rough sleepers find somewhere to sleep indoors.
Gritters will be out on some roads in Torbay in Devon.
Torbay Council has also put in place additional accommodation for homeless people.
The council said warm spaces were also available across Torbay.
A spokesperson said: "They are free to use, and visitors can have a hot drink. There may be food on offer or activities to enjoy. They may also be able to signpost people to other support if needed."
Devon County Council said it had "arrangements in place to maintain services wherever possible, and prioritise according to assessments of risk and need where necessary".
The Cornwall Partnership NHS Foundation Trust and the Cornwall and Isles of Scilly Integrated Care Board issued a joint statement, in which said they would make sure "vulnerable patients and members of the community know what they can do to stay warm and well".
The statement said: "While we'll be checking in more frequently with our most vulnerable, we'll also be making sure they have access to winter vaccinations for flu and Covid, advice on staying warm, and know how to access other services and support, as well as warmth banks."
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