‘Cool start to May’: Weather system to move in over Mother’s Day weekend as region sees below seasonal temperatures

Mother's Day Sunday is shaping up to be below seasonal with a chance of rain. Here's CTV London's Reta Ismail.

Whether you’re visiting family at home or planning to head out to brunch on Mother’s Day Sunday, make sure to pack an umbrella as it will be a soggy day in the region.

“We are not quite reaching our daytime high today. Continuing to struggle in terms of our temperatures and tonight will drop to an overnight low of about two degrees [Celsius],” said CTV News London’s Reta Ismail. “That is below where we’re supposed to be this time of year.”

Wednesday’s daytime high will reach 12 C, but London’s average temperature for this time of year is 18 C. The overnight temperature will dip to 2 C, with a risk of frost.

Ismail says it’s not all bad news however, as there will be plenty of sunshine to start the day on Thursday with a high of 13 C, but clouds will roll into the region late in the afternoon with a 30 per cent chance for rainfall.

“That unsettled pattern will continue as we head into Friday. We have an upper-level trough, and it is causing that instability in the forecast right across southwestern Ontario,” Ismail said.

Ismail says a weak low-pressure system will move into the region on Friday with a high of 14 C, bringing along light rainfall in the morning. Afterwards, a second system will move in behind it.

“Unfortunately looks to be moving in late day Saturday into Sunday morning, and of course that is Mother’s Day. So, we are expecting some showers passing showers Saturday evening and Sunday morning,” she said.

Looking ahead to Saturday, temperatures rebound to seasonal with a high of 18 C and a mix of sun and cloud with a 40 per cent chance of rain. The 40 per cent chance of rain continues overnight with a low of 8 C.

Temperatures cool slightly on Mother’s Day Sunday with a high of 13 C, cloudy skies and a 30 per cent chance of rain.

Here’s a look at London’s long-range forecast

Wednesday: Mainly sunny. Wind becoming northwest 20 km/h this afternoon. High 12. UV index 6 or high.

Wednesday night: Mainly cloudy. Wind northwest 20 km/h becoming light this evening. Low plus 2 with risk of frost.

Thursday: Sunny. Increasing cloudiness near noon then 30 percent chance of showers in the afternoon. Wind becoming west 20 km/h late in the morning. High 13. UV index 5 or moderate.

Friday: Cloudy with 30 percent chance of showers. High 14.

Saturday: A mix of sun and cloud with 40 percent chance of showers. High 18.

Sunday: Cloudy with 40 percent chance of showers. High 13.

Monday: A mix of sun and cloud. High 13.

Tuesday: A mix of sun and cloud. High 14.