MONTREAL -- Montrealers may have seen their region was under a major storm alert Monday, but that doesn't mean they were prepared for what actually arrived.

Around noon, hail began pelting the city so hard that people described having to run suddenly for shelter.

The severe thunderstorm watch was in effect for most of Monday for the Greater Montreal area, according to Environment Canada. It ended around 6:30 p.m.

"Today, conditions are favourable for the development of severe thunderstorms capable of producing strong wind gusts, large hail and heavy rain," the agency notes.

"Remember, severe thunderstorms can produce tornadoes."

Some noted on social media that this was just the latest of some wild weather swings in the last few weeks.

Environment Canada says it recommends against water-related activities during a thunderstorm watch as there can be violent or sudden gusts of wind that move over bodies of water.

"Lightning kills and injures Canadians every year," it states. "Remember, when thunder roars, go indoors."

The agency had previously issued a severe thunderstorm warning for the area, but lifted it shortly before 1 p.m. The warning was back in effect later, with more rain in the forecast for late afternoon.

Severe thunderstorm watches are issued when atmospheric conditions are favourable for the development of thunderstorms that can include damaging and torrential rainfall. 

--With files from Selena Ross