Top York temperature forecast today is 11C in UK while County Down was yesterday 's warmest at 13C . But overnight frosts are predicted for rest of week - with heavy showers , thunder and hail expected today . Environment Agency and Natural Resources Wales have more than 25 flood alerts and warnings in place . Met Office says first week of Easter holidays will see 10C highs and mix of clear spells and showers/rain .
Top UK temperature forecast today is 11C in York while County Down was yesterday 's warmest at 13C . But overnight frosts are predicted for rest of week - with heavy showers , thunder and hail expected today . Environment Agency and Natural Resources Wales have more than 25 flood alerts and warnings in place . Met Office says first week of Easter holidays will see 10C highs and mix of clear spells and showers/rain .