SOUTHAMPTON marathon bosses have issued a safety warning over bulky and heavy costumes this weekend, with temperatures set to soar.

Organisers of the ABP Southampton Marathon have also ordered in more than 50,000 bottles of water ahead of Sunday, when temperatures could rise as high as 18C.

Nikki Rees, one of the race directors, said: "While we love fancy dress, we love our runners even more.

"We would urge runners to be careful make sure they don't put themselves in danger.

“The health and safety of our runners and spectators is our number one priority.

"We’ve ordered extra water for the big day and runners will now have an extra water station to top up on the route."

She also urged runners to make sure they are fully hydrated both the night before and on the day of the race, and asked spectators to bring "plenty of fluids".

The warning comes as organisers of the London Marathon, also set to take place on Sunday, also urged their runners to "think carefully" about wearing heavy costumes.

The Met Office is predicting temperatures to soar as high as 23C in London – which would make it the hottest day in the event's history.

The warmest condition the London Marathon, which was founded in 1988, has been run in was 22.2C in 1996 and 2007.

Top tips for runners from the ABP Southampton Marathon Organisers

• Make full use of the water stops along the route – there’ll be nine stations (or five if you’re doing the half or 10k distances) around the city for you to grab a quick bottle

• Make sure you’re hydrated the day before and the morning of the race

• Wear cool, breathable clothing to keep you cool

• Where possible, keep in the shade before the race so you’re not starting hot and flustered

• Consider using a water belt, hydration pack or hand-held water bottle if you think you might need extra water between the water stations

• Use sunscreen – it may only be April but you’ll be out in the sun for several hours