High temperatures Thursday of around 72 degrees at the beaches, up to 78 inland, 79 to 84 degrees in the western valleys, 90 to 95 degrees near the foothills, 90 to 98 degrees in the mountains and 107 to 112 degrees in the deserts are expected to rise throughout the remainder of the week as high pressure builds aloft, according to the National Weather Service.
But forecasters urged those seeking a break from the heat at the beaches to watch out for strong rip and longshore currents Thursday, along with above average surf with surf that could reach 8 feet. A NWS beach hazards statement will remain in effect through Thursday evening.
High temperatures in inland areas are expected to increase to 10 to 20 degrees above normal Friday and Saturday. A NWS excessive heat warning for the deserts is set to take effect at 10 a.m. Friday and extend until 8 p.m. Sunday. A less severe heat advisory for mountain locales lower than 5,500 feet will run concurrently.
“The first heat wave of the season is approaching and the effects of the heat will be magnified since temperatures at the end of May were near normal,'' according to the weather service. “High temperatures will be 10 to 20 degrees above average Friday and Saturday, and people may mot yet be acclimated to hot weather.''
High temperatures of 114 degrees are in the forecast Friday and Saturday for the Borrego Springs area, and Julian could reach 96 degrees Friday and 94 degrees Saturday.
Higher than average temperatures are also expected along the beaches as a strong high pressure ridge over the southwest states brings warm conditions to Southern California.
“Although cooler than inland locations, even coastal locations will see a warmup to above normal readings, with highs in the 70s to lower 80s,'' according to the weather service.
Forecasters said Sunday would be slightly cooler, but temperatures would still be well above average for early June.
The NWS urged residents to protect themselves and their loved ones against dehydration, heat stroke and other heat-related illnesses. They were advised to stay well-hydrated, avoid working in the sun, check on neighbors and relatives -- especially the elderly -- and provide plenty of water to pets and livestock.