(CNN) It's mid-May, but winter apparently is not finished with parts of the Northeast, which could see yet more snow this week.

Cold air coming in from Canada is likely to cause a mix of snow and rain in higher elevations of New Hampshire, Vermont and much of northern Maine by early Tuesday, CNN meteorologist Gene Norman said.

"It wouldn't be surprising to see flakes flying in places like Montpelier (Vermont) and Portland, Maine," Norman said, adding that if there is measurable snowfall in Portland, it would be the latest in the year that the white stuff has fallen since May 11, 1945.

That's after a miserable Mother's Day of of sleet and snow in parts of western Massachusetts. That was produced in part by the same low-pressure system that triggered flooding rains and some severe storms through the Southeast.

Mississippi Gov. Phil Bryant on Sunday issued a state of emergency following the strong storms and flooding that started Wednesday, with multiple counties reporting major flooding. Damage possibly caused by tornadoes was reported in two counties, the governor's office said in a press release.

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