The National Weather Service has issued wind chill advisories for Thursday night for Lewis County and much of St. Lawrence County.
The wind chill advisory for northern (think Massena area) and southeastern (think Star Lake) St. Lawrence County starts at midnight and goes until 10 AM Friday. Wind chills as low as 25 to 30 below zero are expected.
Wind chills will generally be coldest from 5 AM on.
For Lewis County, the advisory kicks in at 10 PM Thursday and runs to 10 AM Friday. Again, wind chills as low as 25 below zero are expected.
Setting aside the wind chill, the overnight lows will be zero or below right through Sunday night.