The temperature will keep dropping in Calgary, and will bring lots of rain. Tuesday will be mostly cloudy, with just a high of 18 C. There is the risk of late-day thunderstorms again, and by tomorrow night, the rainfall will become more consistent and widespread. Ten millimetres of rain is likely on Tuesday night. The on-and-off rain will push through Wednesday and Thursday. It will be heavy at times, with around 10 millimetres of rain possible each of those days. The daytime high will drop to 13 C by Thursday. The city is expected to start drying out and warming up on Friday. Saturday and Sunday night came with thunderstorms in and around Calgary. Matt Melnyk snapped a stellar lightning shot near Airdrie.