There are warnings for people to avoid swimming in lakes, rivers and other open water.
It follows the death of 17-year-old Russell O'Neill who lost his life over the weekend, swimming in a quarry near the Malvern Hills in Worcestershire.
Charlotte Grant reports.
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Dry morning with plenty of sunshine. Cloud will gradually thicken into the evening but it will remain largely dry.
It will be a fine morning with sunshine but cloud will increase with patchy light rain reaching some areas throughout the day.