A rain and wind storm swept through New Brunswick on Wednesday, but temperatures quickly started dropping early on Thursday.
Schools in the Anglophone South, Anglophone East, Anglophone North and Francophone Northeast districts are closed.
Francophone South closed all schools as well, except for those in the Fredericton and Oromocto area.
Francophone Northwest and Anglophone West schools are open, with some bus delays.
Environment Canada issued a flash freeze warning for much of New Brunswick, saying pooling water, slush and falling precipitation will freeze as temperatures drop.
There has also been flooding, and in Sussex, at least 12 roads have been closed.
CBC meteorologist Tina Simpkin said the cold front was quickly changing rain to snow.
Temperatures that were as high as 11 C in some areas on Wednesday are expected to fall between -6 C and -14 C by Thursday afternoon.
According to the N.B. Power website, more than 7,000 customers are without power.