The National Weather Service warns that hot conditions up to 98 degrees will be present for the San Diego County Mountains 12 p.m. today until Thursday 8/17/23 at 8 p.m. Stay inside or in shaded areas. Drink lots of water. If you feel sick from the heat, call 9-1-1. Never leave young children or pets alone in vehicles. Find a cool place to go and tips to beat the heat at www.coolzones.org. Visit the National Weather Service for more information, updates, and a map.