Residents across southwestern Ontario can expect several days of sunshine and rising temperatures this week before cloudier conditions and a chance of showers arrive later in the forecast. Tuesday is expected to be sunny after any morning fog dissipates. The daytime high is forecast to reach 27 C, with a humidex value of 30. The UV index is 9, considered very high. Clear conditions are expected Tuesday night with a low of 16 C. The warm weather is expected to continue Wednesday, with sunny skies and a high of 30 C. Clear skies are forecast overnight, with temperatures dipping to 17 C. Cloud cover is expected to increase Thursday, when Environment Canada is predicting a 40 per cent chance of showers and a high of 28 C. The risk of showers is expected to persist into Thursday night, with a low of 18 C. The workweek is set to end under mostly cloudy skies Friday, with a 40 per cent chance of showers and a daytime high of 24 C.