SAN DIEGO (FOX 5/KUSI) -- A heat wave brought record-breaking temperatures to parts of the region Friday and hot weather is expected to continue throughout the weekend. Some areas, specifically the San Diego County foothills, are now showing chances of isolated showers and thunderstorms Saturday, according to the National Weather Service. Time-lapse: Crescent Moon dips behind Oceanside’s singed pier diner These storms could bring locally heavy rainfall, "erratic gusty winds," as well as lightning, meteorologist predicted earlier Saturday. Areas that may be impacted include San Diego's valleys, mountains and deserts. For example, Borrego Springs, Julian, Mt. Laguna, Campo and Palomar all had chances of storms ranging between 20% and 22%. Further in, places like Alpine, Ramona and El Cajon had a 10% to 16% chance for storms. Saturday afternoon, the National Weather Service in San Diego issued a Severe Thunderstorm Warning in San Diego's East County for the area between Julian, Descanso and Pine Valley. That warning calls for wind up to 60 mph, quarter sized hail and is in place until 4 p.m. (National Weather Service) The weather service says high temperatures are still expected to be above average Saturday. Areas west of the mountains may even see temperatures 20 degrees higher than average. Stay cool out there, San Diego.