Montrealers can expect a warm, sunny start to the weekend before heavy rainfall sets in. Clear skies and a low of 6 degrees Celsius on Friday night are forecast, leading to an above-seasonal high of 21 degrees Celsius on Saturday. The normal high for this time in April is 12 degrees Celsius. The sunny skies should bring some added heat, but it’s not expected to last long. A special weather statement has been issued by Environment and Climate Change Canada (ECCC) for Saturday evening into Sunday. The agency warns that 15 to 25 millimetres of rain could be on the way to some regions of southern Quebec. Roughly eight millimetres are forecast for the Greater Montreal area, along with a low of 6 degrees Celsius on Saturday night. The mercury is expected to move to a daytime high of 7 degrees Celsius on Sunday, before dropping to a nighttime low of -1 degree Celsius. The low is typically 2 degrees Celsius at this time of year.