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Runners, most bundled up for the freezing temperatures, leave the starting line for the Louisiana Marathon's Quarter Marathon and 5K, Saturday, Jan. 13, 2018.

A blast of cold air -- preceded by a chance of severe weather -- is headed for south Louisiana this weekend with the New Orleans Saints set to host the Los Angeles Rams in the NFC Championship game Sunday.

Temperatures eclipsed 70 degrees in some parts of south Louisiana on Friday, and the weather is forecast to turn ugly with a slight risk of severe weather early Saturday, according to the National Weather Service. 

"Guidance still suggests that a line of showers and storms will move through the area Saturday morning with strong straight line winds as the primary threat," the NWS said in its Friday morning forecast. "The tornado risk is low but a isolated tornado cannot be ruled out."

There's a 90 percent chance of rain on Saturday with wind gusts as high as 30 mph later in the night as the cold air arrives and lows dive into the 30s.

The sun will return Sunday, but highs will stay in the 40s, setting the stage for freezing temperatures Sunday night. Lows will drop into the mid-30s for New Orleans and the low-30s for Baton Rouge on Sunday night, according to the forecast.

"This Arctic air will only be a glancing blow and short lived as we warm up quickly on Monday," NWS forecasters said.