At least three British soldiers fainted Saturday during the final rehearsal in front of Prince William for the annual Trooping the Colour parade.
The guardsmen were wearing woolen tunics and slacks and bearskin hats in the nearly 90-degree London heat for what is known as the Colonel’s Review.
William later tweeted, "A big thank you to every solider who took part in the Colonel’s Review this morning in the heat. Difficult conditions but you all did a really good job. Thank you."
He later added, "The hard work and preparation that goes into an event like this is a credit to all involved, especially in today’s conditions."
The Prince of Wales was also dressed in his full military regalia amid London’s hottest temperature of the year so far.
More than 1,400 soldiers of the Household Division and the King’s Troop Royal Horse Artillery took part in Saturday’s parade and were reviewed by William who is honorary Colonel of the Welsh Guards.
James Calford, 18, the youngest soldier who participated in the Colonel's Review, likened it to "being stood in a sauna with a 200kg dumbbell in your left hand," according to the Daily Mail.
A military trombonist who fainted appeared to attempt to continue to play after falling to the ground as medics rushed to help him.
London recorded its hottest temperature in history — 104 degrees — last summer.
The UK Health Security Agency has issued a hot weather alert for south England, BBC News reported.
Trooping the Colour, which celebrates the British monarch’s official birthday each June, will take place on June 17th and will be overseen by King Charles III.
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