We know that the British weather can be unpredictable.
The Met Office will issue warnings when they believe there is "severe or hazardous weather which has the potential to cause danger to life or widespread disruption to communications or transport." All severe weather warnings are put on the Met Office's website and they are usually widely publicised in any weather forecast on TV or radio. Weather warnings cover problems such as severe gales, heavy rain or snow, icy roads, thunderstorms and lightning, dense fog and also extreme heat and sun.
Useful websites with weather information include: