SAN DIEGO — A late-spring hot spell kept much of San Diego County sweltering once again Tuesday.

In the inland valleys and mountains, the heat wave generated temperatures topping out in the high 80s, 90s and triple digits this afternoon, according to the National Weather Service. In the local deserts, the thermometer readings climbed past the 110-degree mark, the federal agency reported.

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Along the coast, conditions were considerably more comfortable, with mercury readings maxing out in the mid-60s to high 70s.

One East County town, Campo, logged an afternoon high of 102, which surpassed the prior June 11 record of 100 degrees, set in 1979. El Cajon, meanwhile, tied its existing milestone maximum temperature for the date -- 91, last recorded in 1995.

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Other notably toasty temperatures included 114 degrees in Ocotillo Wells; 113 in Borrego Springs; 98 at Ramona Airport; 97 in Escondido; and 95 in Alpine and San Pasqual Valley.

News 8's Marcella Lee found the temperature at over 106 at the Rincon Fire Station Tuesday afternoon.

Coupled with low humidity levels, the sizzling conditions created elevated wildfire risks in the region and posed potential health hazards due to environmental exposure, according to meteorologists.

The extreme warmth prompted the weather service to issue an excessive- heat warning, effective through 8 p.m. Wednesday in the deserts. In the inland valleys, a less urgent heat advisory will remain in effect until 9 Tuesday evening.

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Temperatures are expected to diminish significantly later in the week as the high-pressure system enveloping the county dissipates.