For some areas, especially in southwestern Ontario, Monday will be one of those unique days where the high temperature occurs in the early morning hours.
However, the lingering warmth will come to an abrupt end as a cold front sweeps across southern Ontario from the west, sending temperatures falling through the day.
Scattered showers will accompany the front as it traverses the province, especially in the afternoon and evening. We’ll see afternoon temperatures in the low- to mid-teens for much of the region.
The Greater Toronto Area (GTA) will see rain moving in during the afternoon, while a strong southwesterly flow ushers in warm temperatures. This could be the first day that the City of Toronto reaches 20 degrees.
TUESDAY AND BEYOND: ONCE AGAIN, A COOLDOWN RETURNS
The upper-level ridge that brought us a warm weekend will move downstream and allow an upper-level trough to take its place. This trough will bring much cooler air, making for chilly conditions by midweek.
By Tuesday night, a quick burst of Arctic air moves into the lower Great Lakes region with temperatures falling around the freezing mark. We could see the potential for snow across central and southern Ontario throughout Tuesday overnight.
Temperatures could be up to 10°C below seasonal by Wednesday. In fact, the upcoming streak of below-seasonal air will put parts of southern Ontario on par with the regions closer to the Arctic Circle. London, Ont., and regions near the Arctic Circle can expect a high of about 2°C on Wednesday.
This spell of below-seasonal conditions looks to continue through the beginning of May.
Stay with The Weather Network for the latest conditions across Ontario.