07/12/2012 10:37 EDT

Edmonton Storm: Hail Hits, Floods Trap Drivers (PHOTOS, VIDEO)

UPDATE: Environment Canada issued a tornado watch for the region northeast of the Edmonton Thursday afternoon, Global News reported. Residents are urged to monitor weather closely and head for shelter if severe weather approaches.

Beautiful summer weather gave Edmonton the cold shoulder as hail, thunder, lightning and floods hit the city in the wee hours of Thursday morning, Global News reported.

The hail, which some say reached the size of quarters, surprised many Edmontonians, who had experienced hot and humid weather this week. But most hail storms occur during hot summer months because the warm weather produces the strong thunderclouds needed to create it, USA Today says.

Stunning photos of ice-covered lawns popped up on Twitter, but the storm did much more damage.

It flooded construction sites and streets, trapping at least 18 cars, according to CBC. Firefighters spent Thursday morning rescuing people from their submerged vehicles. No injuries were reported.

The nasty weather partially closed Whitemud Drive and Mill Woods Road, according to the Edmonton Journal.

What does Mother Nature have in store for Edmonton later today? A 60 per cent chance of more thunderstorms and a high of 30 C.

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