For once, a May Long Weekend that actually looks at least partially nice!
However, as is the case with most May Long Weekends, some stormy weather must occur. That stormy weather will arrive Sunday night with rainy and windy conditions likely early Monday. Significant moisture streaming northwards from the US combined with convective activity will allow for locally significant rainfall accumulations. A few embedded thunderstorms are also not out of the question. As a result, rainfall forecasts are a little tricky at this time. Additional showers and embedded thunderstorms are possible late in the day on Monday. Along with the rain, it will also be quite windy with sustained winds of 30-45 km/h. As the event draws closer, I'll provide updates in the comments.
Cooler, below normal temperatures return for mid week before warmer weather arrives for next weekend.