After a warm week in which we saw the hottest April day since 1949 with 29.1°C recorded at St James’s Park in London, the warm conditions are forecast to stretch into the weekend, albeit at not quite the same intensity. There were a number of weather station records set stretching from Yorkshire to Devon, including Sheffield which recorded 26.4°C: the hottest April day on record (records from 1883). In total, 64 stations broke their records for warmest April day.

There will be more bright sunny weather for most of the UK on Friday, with just a few showers in the far north of Scotland which should ease through the day and some cloud hugging western coasts. Temperatures won’t get to quite the same level as Thursday, although 24-26 °C is expected quite widely in south-east England with 27 °C and maybe 28 °C possible in London. Northern Ireland and Scotland are likely to see highs of 17-18 °C, particularly in the East.

After a dry and sunny start to Saturday for all parts, thundery showers will start to develop from the midday in central England and Wales, building in frequency and intensity moving north-eastwards though the day. Saturday will be the best day for Northern Ireland and Scotland which should stay dry and mostly sunny through the day. Temperatures will remain at roughly the same as Friday in the south of the UK, with values pushing slightly higher in northern England and southern Scotland where the low 20s could be recorded.

With the London Marathon on Sunday, runners and spectators will be keeping a close eye on the weather. The thundery showers will continue to move north-eastwards overnight and into the morning with brighter conditions behind them. Further bands of showers could move in from the west later in the day. Temperatures are likely to still be high and after a humid start, temperatures are likely to reach 22 °C with a chance of 23 °C, although trackside measurements may exceed these values. According to Met Office records, the warmest London marathon on record was in 1996 when it reached 22.7 °C in St James’s Park. Elsewhere temperatures will have started to decline slightly with high teens in large parts of England and Wales and mid-teens in Northern Ireland and Scotland.   

Met Office Chief Meteorologist Will Lang said: “Many people will be happy to hear that the warm conditions are forecast to stay around for the weekend, although there will be some heavy thundery showers to watch out for at times. If you are out enjoying the weather remember to protect yourself from the sun, which is now at full strength.

“For those running the marathon, make sure you stay up-to-date with the forecast as there will be high temperatures and humidity to contend with. Stay hydrated and listen to advice from the event organisers.”

Advice from Runner’s World to those running the marathon is to be mindful of the impact the warm weather can have on them. Every 2-3 °C rise in temperature above 15°C can slow a runner's pace by as much as 20 to 30 seconds per mile. It is worth considering starting slower than you may have planned. And to make getting to the finish running strongly the main goal, and to run by perceived effort rather than mile splits.

After a dull and cold start to spring it is important to remember that the sun is as strong in April as it is in late August. When outside make sure you protect yourself from the strong UV rays and stay hydrated. More advice on how to stay safe in the sun can be found on our website.

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