Families were stepping outside to temperatures as low as -14C in parts of Norfolk this morning.
The mercury plunged to that level in Marham and Thetford over night while elsewhere temperatures of -10c and -11C were widely recorded.
Even on the coast at Great Yarmouth, the temperature was -7C.
Steve Western, a forecaster at the UEA-based weather service, WeatherQuest, said today will be bright, but temperatures will struggle to reach 1C.
Icy temperatures are again expected tonight and there is danger of freezing rain making roads treacherous across East Anglia from about 6am tomorrow.
Mr Western said: 'After about 9am tomorrow the temperature will rise to 3C or 4C and that will spell the end of this very cold weather. By Tuesday we will be seeing temperatures of 6C to 8C.'
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