More triple-digit temperatures are expected in Riverside County Wednesday — one day after daily heat records were shattered in three county communities, including Palm Springs, where the mercury hit 119 degrees on the second day of a heatwave.

The previous record high for June 15 in Palm Springs was 116 degrees in 1961, according to the National Weather Service. Records have been kept consistently in Palm Springs since 1922.

The high in Idyllwild was 99, breaking its record for June 15, which was 98 in 1961. The weather service has kept records in Idyllwild consistently since 1943.

The temperature reached 107 in San Jacinto, breaking the previous 103- degree record in the city set in 2007. Records have been kept consistently there since 1948, according to forecasters.

A ridge of high pressure strengthened and expanded over the Southwestern United States this week, ushering in the sweltering conditions that are expected keep Riverside County in the triple digits during the daytime hours for the entire week.

Wednesday’s forecast calls for temperatures of 100-108 in the Riverside valleys and Inland Empire, 96-106 in the mountains, 109-114 in the San Gorgonio Pass near Banning and 112-117 in the Coachella Valley.

Tuesday’s highs in Riverside County also included 102 in Anza, 103 in Beaumont, 104 in Riverside and 105 in Lake Elsinore.

The mercury also reached 106 in Pinyon Pines, where firefighters are continuing to battle a 400-acre wildfire that was sparked Sunday in the San Bernardino National Forest.

An excessive heat warning began Monday morning and will continue through 9 p.m. Sunday in the Coachella Valley and the San Gorgonio Pass near Banning.

The warning will also include the Riverside metropolitan area and the Riverside County mountains starting at 10 a.m. Tuesday and lasting through 9 p.m. Saturday.

The heat in the Coachella Valley could continue climbing, with forecasters saying Friday could see a high of 122.

The weather service said the extreme heat will significantly increase the potential for heat-related illnesses, particularly for those working or participating in outdoor activities.

J.F.K. Memorial emergency room professional Dr. Timothy Rupp says simple solutions can detur a trip to the ER when experiencing heat illness-related symptoms.

“First and foremost, when someone is starting to feel fatigued, perhaps nauseated, dizzy, headache, that’s when they should immediately take shelter from the heat, try to stay hydrated and stay in a cool dry environment at least for a little while to see if their symptoms get better.”

Dr. Rupp continued, “if after a few minutes they’re not starting to feel better or perhaps they’re feeling worse, then that’s an indication that they probably need to seek medical attention.”

People should be prepared to drink plenty of fluids, stay in an air-conditioned room, stay out of the sun and check up on relatives and neighbors.

While young children and pets should never be left unattended in vehicles under any circumstances, the weather service said that’s especially true during warm or hot weather — when car interiors can reach lethal temperatures in a matter of minutes.

The county recently opened cooling centers in multiple locations, where residents who don’t have access to air-conditioning can stay during the heat of the day. A complete list of options is available at www.capriverside.org/cool-centers.

Intense Heat Wave Shatters Daily Temperature Records Across Riverside County