LOUISVILLE, Ky. (WDRB) -- A heat warning is being issued for Louisville's homeless population on the first official day of summer.

Wednesday has the potential to be another Operation White Flag Day.

A white flag is put out at Wayside Christian Mission on extremely hot days as a sign welcoming the homeless to come inside and cool off.

For many people, hot weather means cranking up the A/C and cooling off in the pool, but for Louisville's homeless population, those aren't easy options.

Temperatures on Wednesday are expected to climb into the 90's, which is why city officials will likely issue an Operation White Flag Day.

On days the temperature is below 35 degrees or above 95 with the heat index, a white flag flies outside each participating shelter to let people know they can stay there. The shelters include Wayside Christian Mission, the Salvation Army and Saint Vincent De Paul.

A white flag doesn't always mean a bed is available, but it does offer up a cool, safe place to stay and avoid overheating.

Operation White Flag is funded by Metro Government, but those funds aren't always enough.

Officials say it's important for shelters to stay open regardless of the lack of funding.

Natalie Harris, of Coalition for the Homeless, said "We get about $5 a night for the shelter stays from the city, but it costs the shelters anywhere from about $22-$35 a night for extra food."

If you need a bed or know someone who does, it's best to request one through the Coalition for the Homeless right at 10 a.m. before they fill up.

To make a bed reservation, the number is 502-637-BEDS (2337).

Officials here at the shelter say they could always use volunteers.

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