Himachal Pradesh is set to witness heavy rain, hailstorm and thunderstorm on Sunday as the state's Meteorological Department has issued a yellow weather alert for today.As per the department, yellow alert has been issued for Shimla, Kullu, Solan, Mandi, Sirmour, Kinnaur and Lahaul and Spiti districts. Heavy rain along with hailstorm and thunderstorm is expected in isolated places.