SAN FRANCISCO (CBS SF) – Forecasters are expecting unseasonably hot inland weather throughout the Bay Area over the weekend with temperatures in the triple digits, up to 20 degrees higher than normal, according to the National Weather Service.

The high-pressure ridge will bring increased risk of heat-related illnesses for sensitive groups like the young or the elderly, and especially for anyone exposed to outdoor heat on a prolonged basis.

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Pets, crops and livestock may also be at risk due to the heat.

The weather will bring an increased risk of drowning, hypothermia and water rescues on the coast due to an influx of people going to the ocean for the cooler temperatures, weather service officials said.

Temperatures are expected to be hottest on Saturday, although they should remain normal Wednesday, and coastal areas will experience near-normal weather throughout the weekend.

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Many inland areas of the East and North Bay are expected to reach temperatures of 90 to 100 degrees. The southern Salinas Valley and Pinnacles National Park are both expected to exceed 100 degrees.

An excessive heat watch has been issued from Friday afternoon through Sunday evening.

For more information go to www.wrh.noaa.gov/wrh/heatrisk.

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