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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Rather cloudy but mainly dry with some brightness tomorrow.
Frost free tonight then mainly dry and bright tomorrow.
Sutty from the Pets as Therapy charity is one popular visitor on the Children's wards, helping brighten up the day for poorly patients.