Ontario Weather Maps:
Monday:

Southern Ontario will have unsettled weather conditions in the next few days as a trough of low pressure lingers in, bringing thunder, rain and cooler temperatures. Some of the storms may reach severe limits, but most of them should be non-severe. Temperatures will be in the low-mid 20's this week and the weather will stay this way until the trough moves on. Ontario Weather will be tracking down this system.
Monday:

Northern Ontario is not as active as the south today, but it will get MORE rain today. About 5-10mm in most areas (mainly in central Ontario). Temperatures will be in the mid-teens.