Emily Tamminen, programme manager at the Salvation Army in Bradford, said people living on the streets lacked easy access to water.
“The lack of shelter and shade, especially in Bradford city centre, there’s not really a lot of that about,” she said.
“We’ve seen a lot of the guys come in with sunburn as well, quite bad sunburn.
“They’ve been taking the tops off to cool down and then not putting anything on to cover up.”
She said The Orchard – a Salvation Army day shelter and supported accommodation – was getting more people through the door during this latest heatwave.
“Because it’s so hot outside it’s a risk for people, especially if they already have medical needs as well.”
She encouraged people to carry an extra bottle of water to help homeless people who may not have easy access.
Mark Donnelly, from Bradford’s Hope Housing, said the charity had been “running around trying to make sure they all had fans”.
“Another danger is dehydration, keeping hydrated,” he said.
“I just wish we could help everybody.”
If you’ve been affected by some of the issues raised in this article please visit BBC Action Line for advice and support.
