It's not technically winter yet, but city of Hamilton officials have issued a cold alert for Wednesday morning.

Such alerts are issued when weather conditions are expected to be below —15 C or —20 C with windchill.

Environment Canada forecasters expect temperatures to drop to —11 C overnight Tuesday with winds gusting up to 50 km/h.

"Wind always makes it feel colder, and increases the risk of frostbite and hypothermia," the city said in a release.

How to keep warm

The alert triggers city notice to social agencies that work with vulnerable and homeless people. If you come across someone in need of shelter, you can call the Salvation Army to report their location: 905-527-1444 Ext. 0.

Rec centres are open during regular hours for people who need a place to be warm, and the MacNab transit terminal is open and heated as long as the HSR buses are running.

To lower the risk, the city issued some reminders and tips for this first cold alert of the season: