Areas of thunderstorms are increasingly likely to develop over the south of the UK or nearby continent late on Sunday and will generally track north or north-westwards, potentially affecting all parts of the UK at some points during this period. Whilst the most intense thunderstorms, in some instances associated with large hail, will most probably be those triggered by the high temperatures of the day over England and Wales, other areas of storms producing heavy rainfall, frequent lightning and strong gusty winds could reach further north at times over Scotland and Northern Ireland. These could occur at any time of the day. Where the storms occur, rainfall totals of 30-40 mm could fall in an hour, with some locations potentially receiving 60-80 mm in 3 hours, although these will be fairly isolated.
Low danger from the sun's UV rays for the average person. Wear sunglasses on bright days. If you burn easily, cover up and use sunscreen.
Moderate risk of harm from unprotected sun exposure. Take precautions, such as covering up, if you will be outside. Stay in shade near midday when the sun is strongest.
High risk of harm from unprotected sun exposure. Wear sunglasses and use SPF30+ sunscreen. Cover the body with sun protective clothing and a wide-brim hat. Reduce time in the sun from two hours before to three hours after solar noon.
Very high risk of harm from unprotected sun exposure. Take extra precautions. Use SPF30+ sunscreen, a shirt, sunglasses and a hat. Do not stay out in the sun for too long. If you have to be outside avoid the sun from wo hours before to three hours after solar noon.