It isn’t quite summer yet, but the Southland will find itself baking in summer-like heat next week, with triple-digit temperatures anticipated in the valleys and mountains, while even downtown could hit the upper 90s.
The forecast is raising fears of heat-related illnesses, strain on the power grid and the possibility of brush fires that could quickly spread in the hot and dry conditions.
The National Weather Service has already issued an excessive heat watch that will be in effect from Tuesday morning through Friday night across the valleys and mountains. Forecasters said mountain and valley areas will face “dangerously hot conditions,” with temperatures possibly reaching 109 degrees.
The watch will be in effect for the coastal region, stretching from the beaches into downtown Los Angeles, from Tuesday morning through Wednesday evening, with highs potentially reaching 98 degrees.
“Tuesday through Thursday should be the hottest, when highs between 100 and 110 and minimum humidities between 5 and 15 percent will be common over most mountains and lower mountains,” according to the NWS. “Monday night through Tuesday night is of particular concern, when north winds increase and enhance the warming and drying over the coasts and nearby valleys.”
For interior valleys, “hot, dry and breezy conditions” could create critical fire-danger conditions.
“There is still some uncertainty as to when the heat will relax, but there is a potential for little change through next weekend, especially for interior areas,” according the weather service.
Coastal areas will see relief a little earlier, with onshore flow expected to return by late Wednesday, bringing a return of the marine layer that will bring temperatures down.
The California Independent System Operator, which manages the state’s power grid, released a statement Friday saying the agency “could take a number of actions to reduce demand and access additional energy” between Tuesday and Friday. The agency declared a “restricted maintenance operation” condition that will be in effect from noon to 10 p.m. Tuesday through Friday due to the forecasted high temperatures and demand. The declaration warns that all available resources will be needed to maintain supply, and calls on suppliers to defer scheduled maintenance on generators and transmission lines if possible.
“It is still too early to know the precise impact that next week’s high temperatures will have on the electricity grid,” according to Cal-ISO. “But the ISO is closely monitoring conditions and the anticipated increase in demand for electricity and will issue additional public notifications as warranted.”
If necessary, the ISO could issue a Flex Alert, which is a voluntary call for residents to conserve power during peak hours to reduce strain on the grid.
The NWS warned that extreme heat will “significantly increase the potential for heat-related illnesses.”
“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,” according to the NWS. “Young children and pets should never be left unattended in vehicles under any circumstances. This is especially true during warm or hot weather when car interiors can reach lethal temperatures in a matter of minutes.”