SAN FRANCISCO (KRON) — A heat advisory is in effect for the Bay Area on Saturday, according to the National Weather Service.

A fire weather warning was also issued for the East Bay hills.

Both advisories are active until 9:00 p.m.

The public is advised to stay in the shade and drink plenty of water throughout the day to lessen the chance of heat illness, weather service officials said.

There is an increased risk of drowning and water rescues as people seek cooler areas, officials said.

The weather service says hot weather is caused by a strong, high pressure system over the desert southwest that came into the Bay Area, sending temperatures into the 100-degree range.

Just before 1:00 p.m., the Santa Clara and North Bay valleys were added to the heat advisory list.

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