As temperatures in the city hit 32° on Wednesday, police advised residents to watch out for opportunist burglars taking advantage of open doors or windows.
'Heatwave Action’ warning from Met Office
The warning followed several burglaries in the Shirley area of Southampton since late June.
"During hot weather people sometimes forget they have left doors or windows open or unlocked," said Detective Constable Abigail Leeson.
"We always advise people that, unless they are in the same room or right nearby it is best to shut and lock windows and doors, especially on the ground floor.
"It only takes an opportunist burglar seconds to sneak in through an open door or window and make off with any small valuable items such as laptops, wallets, purses and mobile phones.
"As well as shutting windows and doors when you are not nearby, I would also suggest that people move valuable items away from windows where they can be seen easily.
"It's also worth registering your items for free on www.immobilise.com. We can then use this to search for items that are stolen and, if we recover them, it helps us to get them back to their rightful owner more quickly."