How hot does it need to be for a heatwave to be declared?
The weather's getting hotter, but how hot does it need to be to be considered a heatwave?
Wales Weather
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'Risk of flooding' as Storm Gerrit set to batter Wales with heavy rain and wind
A yellow weather warning for rain for most of Wales has been issued by the Met Office as Storm Gerrit moves in.
Travel disruption expected as strong winds and flood warnings issued in Wales
The Met Office said "some delays to road, rail, air and ferry transport are likely".