Snow: More than 200 Norfolk schools remain closed
More than 200 schools in Norfolk remain closed due to snow with a yellow weather warning still in place.
Temperatures fell to -8.5C (17F) at about 02:00 GMT at Houghton Hall near King's Lynn - the coldest for two years.
On Tuesday, the North Walsham Covid-19 vaccination centre reopened after closing on Monday.
Temporary Ch Insp Jason Selvarajah said motorists should not "venture out unless it's absolutely necessary".
He said if people "take practical steps to keep themselves safe" then emergency services would not have to "take additional risks to help them".
Overnight snowfall on top of the previous two days's dumps lead to depths of a foot (30cm) in some places.
The Environment Agency has issued one flood warning and nine flood alerts.
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Some 217 schools remained closed, with a further five partially closed, according to the Norfolk County Council school closures webpage.
Norfolk's 14 recycling centres also remain closed.
Andy Ellis, from Norfolk County Council's Highways team, said he was "a little bit concerned" about the low temperatures predicted.
Forecasts suggest some parts of the county could get as low as -10C (14F) overnight with the Met Office issuing a yellow weather warning for snow and ice until 11:00 on Thursday.
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