The heat wave that gripped the area is expected to subside with cooler weather in San Diego County this week and temperatures dropping more than 20 degrees by Wednesday, according to the National Weather Service.

A heat advisory remains in effect until at least 8 p.m. Monday for the cities of Carlsbad, Encinitas, Chula Vista, Vista, Oceanside, San Diego and National City, NWS said.

Record high temperatures were reported Sunday in parts of San Diego County. It was 109 in Escondido, breaking the record for the day of 104 set in 1944. It was 110 in Ramona, breaking the record for the day of 103 set in 2018. It was 105 in Alpine, breaking the record for the day of 104 set in 1984. It was 108 in El Cajon, breaking the record for the day of 104 set in 1984.

San Diego Gas & Electric experienced several power outages during the weekend, with the causes still under investigation. The utility provider broke records for power usage, with 5,032 megawatts of demand at 6:45 p.m. within SDG&E’s service area — shattering the previous record of 4,890 megawatts set on Sept. 16, 2014.

Conditions will slowly cool this week, with downtown highs dropping to 84 on Tuesday and 75 on Wednesday, according to current forecasts.

High temperatures in other parts of the county Tuesday are expected to reach 87 to 91 inland, 90 to 95 in the western valleys, 95 to 100 near the foothills, 89 to 98 in the mountains and 110 to 113 in the deserts, NWS said.

No hazardous marine weather conditions are expected through Thursday.

City News Service contributed to this article.