Wednesday was a dangerous travel day across southern Ontario, as persistent snow squalls throughout the day greatly reduced visibility, leading to several road closures and accidents. Drivers are being urged to consider to postponing non-essential travel until conditions improve Thursday morning.

One of the collisions occurred Wednesday morning, when Wellington County Ontario Provincial Police (OPP) stated two people were sent to hospital with serious injuries following a head-on collision on Highway 6 near Arthur.

For the latest road closures, click here.

SEE ALSO: Ontario: Snow squalls to taper off Thursday, but the bitter cold will continue

"There is reduced visibility due to snow squalls. Avoid the area and if you do not need to travel - stay home," the OPP tweeted, adding that Highway 6 between Side Road 9 and Side Road 10 had been closed for the investigation.

WellingonOPP on scene of a serious MVC involving a sedan and SUV on Hwy 6 north of Arthur. Both drivers were transported to local hospital with serious injuries. There is reduced visibility due to snow squalls.

OPP West Region on Twitter: "#WellingonOPP on scene of a serious MVC involving a sedan and SUV on Hwy 6 north of Arthur. Both drivers were transported to local hospital with serious injuries. There is reduced visibility due to snow squalls. Avoid the area and if you do not need to travel - stay home.^cr pic.twitter.com/vNnXdiiBHs / Twitter" on scene of a serious MVC involving a sedan and SUV on Hwy 6 north of Arthur. Both drivers were transported to local hospital with serious injuries. There is reduced visibility due to snow squalls. Avoid the area and if you do not need to travel - stay home.^cr OPP West Region on Twitter: "#WellingonOPP on scene of a serious MVC involving a sedan and SUV on Hwy 6 north of Arthur. Both drivers were transported to local hospital with serious injuries. There is reduced visibility due to snow squalls. Avoid the area and if you do not need to travel - stay home.^cr pic.twitter.com/vNnXdiiBHs / Twitter"

— OPP West Region (@OPP_WR) OPP West Region on Twitter: "#WellingonOPP on scene of a serious MVC involving a sedan and SUV on Hwy 6 north of Arthur. Both drivers were transported to local hospital with serious injuries. There is reduced visibility due to snow squalls. Avoid the area and if you do not need to travel - stay home.^cr pic.twitter.com/vNnXdiiBHs / Twitter"

EARLY TASTE OF WINTER CREATES HAVOC IN ONTARIO

Drivers: take care on Highway 401 between Putnam and Ingersoll. Our Provincial Communications Centre is reporting 6 crashes involving multiple vehicles in that area in both the EB and WB lanes. Slow down and give yourself extra time to get home tonight. ^dr pic.twitter.com/IsmwqJiNx0

Drivers: take care on Highway 401 between Putnam and Ingersoll. Our Provincial Communications Centre is reporting 6 crashes involving multiple vehicles in that area in both the EB and WB lanes. Slow down and give yourself extra time to get home tonight. ^dr OPP West Region on Twitter: "Drivers: take care on Highway 401 between Putnam and Ingersoll. Our Provincial Communications Centre is reporting 6 crashes involving multiple vehicles in that area in both the EB and WB lanes. Slow down and give yourself extra time to get home tonight. ^dr pic.twitter.com/IsmwqJiNx0 / Twitter"

— OPP West Region (@OPP_WR) OPP West Region on Twitter: "Drivers: take care on Highway 401 between Putnam and Ingersoll. Our Provincial Communications Centre is reporting 6 crashes involving multiple vehicles in that area in both the EB and WB lanes. Slow down and give yourself extra time to get home tonight. ^dr pic.twitter.com/IsmwqJiNx0 / Twitter"

Wednesday was the third day of lake-effect snow for southern Ontario with some hefty snowfall totals expected by Thursday morning. Lake-effect bands off of Lake Huron and Georgian Bay targeting Huron-Perth, Barrie, and parts of southwestern Ontario could drop as much as 30 cm of snow by the time they diminish Thursday morning.

And through the squall we go. Near Ingersoll/Putnam. @weathernetwork #onstorm pic.twitter.com/2RHyGvASyU

And through the squall we go. Near Ingersoll/Putnam. Mark Robinson on Twitter: "And through the squall we go. Near Ingersoll/Putnam. @weathernetwork #onstorm pic.twitter.com/2RHyGvASyU / Twitter" Mark Robinson on Twitter: "And through the squall we go. Near Ingersoll/Putnam. @weathernetwork #onstorm pic.twitter.com/2RHyGvASyU / Twitter" Mark Robinson on Twitter: "And through the squall we go. Near Ingersoll/Putnam. @weathernetwork #onstorm pic.twitter.com/2RHyGvASyU / Twitter"

— Mark Robinson (@StormhunterTWN) Mark Robinson on Twitter: "And through the squall we go. Near Ingersoll/Putnam. @weathernetwork #onstorm pic.twitter.com/2RHyGvASyU / Twitter"

Bowmanville Avenue, poor visibility #onstorm pic.twitter.com/8ePeAQGpfL

Bowmanville Avenue, poor visibility Briar Jamieson on Twitter: "Bowmanville Avenue, poor visibility #onstorm pic.twitter.com/8ePeAQGpfL / Twitter" Briar Jamieson on Twitter: "Bowmanville Avenue, poor visibility #onstorm pic.twitter.com/8ePeAQGpfL / Twitter"

— Briar Jamieson (@mbjamieson) Briar Jamieson on Twitter: "Bowmanville Avenue, poor visibility #onstorm pic.twitter.com/8ePeAQGpfL / Twitter"

Video of a crash outside of #ldnont due to the weather #onstorm if you don't have to drive don't. pic.twitter.com/ThwqglBavf

Video of a crash outside of J P on Twitter: "Video of a crash outside of #ldnont due to the weather #onstorm if you don't have to drive don't. pic.twitter.com/ThwqglBavf / Twitter" due to the weather J P on Twitter: "Video of a crash outside of #ldnont due to the weather #onstorm if you don't have to drive don't. pic.twitter.com/ThwqglBavf / Twitter" if you don't have to drive don't. J P on Twitter: "Video of a crash outside of #ldnont due to the weather #onstorm if you don't have to drive don't. pic.twitter.com/ThwqglBavf / Twitter"

— J P (@BraveTube) J P on Twitter: "Video of a crash outside of #ldnont due to the weather #onstorm if you don't have to drive don't. pic.twitter.com/ThwqglBavf / Twitter"

Driving conditions have deteriorated with the onset of more snow squalls. Slow down, leave extra stopping distance and use full lighting system. Wherever you are going, you will need extra time. #DriveSafe #ONstorm pic.twitter.com/vOLx7oJaHg

Driving conditions have deteriorated with the onset of more snow squalls. Slow down, leave extra stopping distance and use full lighting system. Wherever you are going, you will need extra time. South Simcoe Police on Twitter: "Driving conditions have deteriorated with the onset of more snow squalls. Slow down, leave extra stopping distance and use full lighting system. Wherever you are going, you will need extra time. #DriveSafe #ONstorm pic.twitter.com/vOLx7oJaHg / Twitter" South Simcoe Police on Twitter: "Driving conditions have deteriorated with the onset of more snow squalls. Slow down, leave extra stopping distance and use full lighting system. Wherever you are going, you will need extra time. #DriveSafe #ONstorm pic.twitter.com/vOLx7oJaHg / Twitter" South Simcoe Police on Twitter: "Driving conditions have deteriorated with the onset of more snow squalls. Slow down, leave extra stopping distance and use full lighting system. Wherever you are going, you will need extra time. #DriveSafe #ONstorm pic.twitter.com/vOLx7oJaHg / Twitter"

— South Simcoe Police (@SouthSimcoePS) South Simcoe Police on Twitter: "Driving conditions have deteriorated with the onset of more snow squalls. Slow down, leave extra stopping distance and use full lighting system. Wherever you are going, you will need extra time. #DriveSafe #ONstorm pic.twitter.com/vOLx7oJaHg / Twitter"

Thumbnail courtesy of Mark Robinson.

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