The temperature plummeted to as low as -15 Celsius in Limburg on Monday night and could reach -18 Celsius in the south east tonight, says the KNMI weather bureau.

The severe frost caused the closure of two lanes of the A6 into Amsterdam on Monday afternoon, after heavy frost and a thaw during the day loosened the road surface and turned it into gravel. Traffic is being diverted via the A27 and the A1.
The traffic information service VID says repairs to the A6 cannot be made until the weather improves and the road will remain shut for some days yet.
In Groningen social workers were out looking for homeless people and warning them to use a shelter for the night. And shelters in other cities were opened free of charge.
Penguins moved
In Arnhem, Burgers’ Zoo moved its 48 black foot penguins indoors for the night. The penguins come from the South African coast and cannot withstand such low temperatures.
And the society for the protection of birds is asking people to put out extra feed while the extreme cold continues. ‘With these low temperatures, birds need extra food to keep warm,’ a spokesman told news agency ANP.
Several schools were also closed on Monday because the central heating systems had broken down.