Several meteorologists and police officers are urging Ontarians to stay off the roads — and specifically Highway 401 — amid a mega winter storm that's resulted in local street closures, flight cancellations, and hazardous conditions.

It's a bad day to be travelling anywhere, but one Weather Network meteorologist is advising holiday commuters to specifically avoid Highway 401 east of Toronto through Kingston.

Can’t say this strongly enough - this afternoon and evening will be one of the worst driving situations I’ve ever seen for the 401 east of Toronto through Kingston. Anyone on the road should be prepared to be stranded by blizzard conditions. #ONStorm pic.twitter.com/ViYsqYG5UW

— Chris Scott (@ChrisScottWx) December 23, 2022

Another meteorologist echoed this previous advice, calling travel along the 401 east "hazardous."

A great graphic to reiterate what @ChrisScottWx said earlier this morning. @erinwenckstern @weathernetwork Hazardous travel along #401 east pic.twitter.com/Inavb6wGXe

— Melinda Singh TWN (@WxMelinda21) December 23, 2022

A section of Highway 401 was also closed after a crash involving 12 vehicles this morning. As a result, both eastbound and westbound lanes were closed between London and Tillbury.

#ElginOPP CK Detachment has closed both the E/B and W/B Lanes of the #HWY401 between Tilbury and Victoria, due to a collision involving 12 Vehicles. More updates when available. ^bp pic.twitter.com/Jlcn2Ipn70

— OPP West Region (@OPP_WR) December 23, 2022

Ontario Provincial Police Sgt. Kerry Schmidt told CP24 that there are reports of more than 100 vehicles involved in several collisions along Highway 401.

You don't want to be caught in this. #MiddlesexOPP media officer Cst. Jeff Hare says the 401/402 corridor is one of the worst traffic scenes he's ever seen. Today is a good day to stay home and stay safe. For road closure information, check @OPP_COMM_WR or @511ONWest. ^dr pic.twitter.com/2iKGIpkN2u

— OPP West Region (@OPP_WR) December 23, 2022

While no serious injuries have been reported as of yet, heavy snowfall and strong winds are resulting in a pile-up situation between the Windsor and London corridor.

"Just got off the phone with the communication centre Sergeant in London and OPP across southwestern Ontario are responding to hundreds of collisions right now," Const. Ed Sanchuk said in a video posted to Twitter.

Seriously, if YOU don't need to travel, please STAY HOME. #OPP urging drivers to stay off the roads. #WinterStorm causing zero visibility, slick roadways,and downed trees. Please DO NOT call 911 for road or weather conditions. @511ONWest. #ONStorm @NorfolkCountyCA #NorfolkOPP ^es pic.twitter.com/d1iZPwBDYz

— OPP West Region (@OPP_WR) December 23, 2022

"If you do not need to travel today please stay off the roadways," Sanchuk said. "As you can see right now, the winter storm is causing basically zero visibility."

If you absolutely must get behind the wheel today, the constable suggests reducing your speed drastically because the roadways are slick and full of ice.