MONTREAL -- Montrealers can get ready to break out the shorts and T-shirts as summery warmth gets ready to move in.

After a cool start to the month of May, which featured below average temperatures for the first 12 days, a big warm-up is on the way. May 13 brought Montreal its first 20-degree reading of the month, and marked the start of a stretch of warm days.

Thursday marked the warmest day of of the month so far:

For the next seven days, daytime highs are expected to be in the 20s, with overnight lows staying in the double digits. But the warmest stretch of weather is expected through the first half of next week, where daytime highs could rise into the mid to upper 20s. By Wednesday, Montreal could see a high of 27 degrees Celsius, which would be the warmest day of the year so far.

May wx1

There is still some uncertainty as to whether the warm weather will stick around into the May long weekend. A pattern change could bring cooler temperatures, with the daytime highs slightly below average.

Last year, Montreal recorded 11 days with temperatures into the 20s, and the city saw its first heat wave of the season beginning May 26. The city also recorded its warmest spring temperature of all time - and second warmest temperature reading of all time - on May 27 with a daytime high of 36.6 degrees Celsius.

 May wx2