Hamiltonians can look forward to warmer weather this weekend leading to a significant thaw after the week's deep freeze.

The forecast high for Saturday, Jan. 11 is 9 C and about 10 to 15mm of rain is expected to fall. The above zero temperatures will continue till Sunday with a predicted high of 2 C.

It was only a few days ago residents had to deal with extremely cold temperatures – frozen sidewalks, slips-and-falls, broken pipes. Now, the city is warning that the snow and ice is likely to melt given the warmer weekend weather. Here’s how you can prepare:

  • Keep catch basins clear of snow, ice and debris and uncover fire hydrants near your home
  • If your home has a backwater valve installed on the sewer, follow the manufacturer’s instructions for cleaning to ensure that it is functioning properly
  • Check your sump pump to make sure it is working properly
  • If your home or area is prone to flooding you may want to consider ensuring any valuables are up off of basement floors
  • Keep your eaves troughs clean. When your eaves troughs are blocked, the rain will pour over the edges landing on the ground next to your home. If you have cracks in the concrete wall of your basement or problems with your weeping tile, this water could enter your home

Hamilton Conservation Authority says at this stage the flooding risk remains low.

"It depends on how long we get above zero temperatures, how much rain we get and quickly the rain falls," said Jonathan Bastien, the authority's water resources engineer. "We're going to keep a close eye on [snowpacks]. My message to residents is to watch local conditions and keep kids and pets away from water bodies."

According to Bastien, high water levels are mainly contained within creeks.

This drastic weather change leaves city staff moving from extreme weather cleanup to bracing for a flooding.

'Crews are working proactively to clear catch basins and inspect flooding hot spots across the city.'- Kelly Anderson, Hamilton public works

“While some Hamilton roads crews are continuing cleanup efforts across the city, some have now switched gears to focus on preparing for the milder temperatures this weekend,” says Kelly Anderson, the city’s public works department spokesperson. “Crews are working proactively to clear catch basins and inspect flooding hot spots across the city.”

Hamilton broke a weather record Tuesday with temperatures dipping to -24 C (wind chill -41 C) making it the coldest January 7 on record. Residents had to deal with frigid icy conditions, frozen sidewalks and burst pipes.

The cold weather alert affecting Hamilton and most of Southern Ontario increased the risk of frostbite and hypothermia, while city paramedics reported higher slip-and-fall incidents.

Flood risk

Now, predicted warmer weather and a weekend downpour are creating a flood risk in the city. Temperatures are forecast to reach a high of 7 C on Saturday, and 10 to 30 mm of rain is predicted to fall on Friday and Saturday, with most of the rain occurring on Saturday. 

The melting of the city snowpack increases the risk of flooding. Environment Canada also warns there is a risk of freezing rain starting Friday night.

The changes may be drastic but not quite unexpected for the season, says Ross Hull, CBC News meteorologist.

“The winter is often a time of extremes when it comes to weather. It’s not necessarily unusual to experience wide contrasts in weather in the Southern Ontario region,” Hull said.

This week, however, what many cities experienced was an extreme weather event. “It wasn’t just how cold it was, it was the wind. Also, it was how quickly the arctic air moved in. Within a matter of hours, we were below freezing.”