WASHINGTON -- Newsflash! It's hot outside. But you already knew that.

A heat advisory is in effect for the District of Columbia and its Maryland and Virginia suburbs until 10 p.m. Wednesday -- and go back into effect noon Thursday through 10 p.m. Thursday -- with temperatures expected to head into the upper 90s and the heat index register somewhere between 100 and 105 degrees.

To beat the heat, you should stay indoors in an air-conditioned spot and drink plenty of liquids to avoid the risk of hyperthermia.

Metro announced Wednesday morning that its prohibition on drinking water on Metrorail and Metrobus will be lifted during the duration of the heat advisory. The consumption of other liquids -- and eating -- on public transit will still violate Metro's standing rules.

Stay cool, D.C.!

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