A Scarborough family was shocked when the tree in their backyard exploded during the thunderstorm that hit the GTA on Sunday.

The Muldoon family was at church when the lightning strike occurred in the backyard of their Avalon Boulevard home Sunday morning.

"The power of nature is incredible. I'm glad we weren't here and I'm glad no one was in the backyard," said Sean Muldoon.

Stephanie Breene lives across the street and saw the lightning hit the tree.

"I heard a little bit of thunder and then I saw a fireball hit the tree. It looked like it went in and it just exploded," said Breene.

At a neighbouring home, a piece of wood shot right through the window of a 10-year-old girl's bedroom. The girl wasn't home at the time but the impact left shattered glass all over her room.

Ken Bowman was inside the house at the time and said it was a very scary experience.

"We are so lucky no one was in there. If this happened at night when (we were) sleeping (it) would have been real nightmare," he said.

The storm came from Michigan and passed over southwestern Ontario in the late morning and early afternoon, with cities such as Kitchener, Waterloo and Hamilton also experiencing intense lightening and golf ball-size hail.

The unusual weather was captured on video by MyNews contributor Alex Tiffen, who filmed the hail raining down on a backyard in Kitchener, Ont.

Toronto is expected to remain cloudy and warm Sunday night with a low of 14 C. There is a 30 per cent chance of showers for the city in the evening.

A risk of a thunderstorm remains for the GTA early Monday morning, with the temperature expected to reach a high of 19 C.

With files from CTV's Naomi Parness