Air temperatures will drop to below -25 degrees (c) across Estonia on Tuesday night and as low as -30 degrees (c) in eastern Estonia. The Environment Agency is asking people to keep themselves up to date with the weather.
The Enviroment Agency says temperatures will stay low in some areas until January 5.
"The east wind is gusty and deepens the feeling of cold," it says.
A level two (orange) "dangerous" weather warning has been issued in Lääne-Viru and Ida-Viru counties. A "potentially dangerous" weather warning is in force across the rest of the country.
The agency urges people to keep up to date about the weather conditions.
The only area unaffected is the western islands, where temperatures will not drop as low.
More information can be viewed on the agency's website.
Editor: Helen Wright