Environment Agency staff have spent the day dealing with an emergency at a canal in Grantham after hundreds of dead fish were discovered this morning.
It's thought they died through lack of oxygen caused by the hot weather.
Chemicals have now been added to the water to bring the oxygen levels back to normal.
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Outbreaks of rain first thing in the east will ease through the morning, but remaining largely cloudy throughout the rest of the day.
Another cloudy day with outbreaks rain or drizzle and mist in the morning. Some heavier bursts of rain possible at first.
Another cloudy day ahead with outbreaks rain or drizzle and mist in the morning.