A period of cooling that made for a fairly temperate start to summer in the San Diego area this week will give way to intensifying heat over the next several days, according to meteorologists.
A low-pressure trough along the California coast will slowly weaken as a large ridge of high pressure builds over the Pacific Northwest during the weekend, bringing local temperatures 5 to 10 degrees above normal to Southern California, according to the National Weather Service.
Due to the potential for dangerously hot conditions, an NWS excessive-heat watch will be in effect for the local deserts from 10 a.m. Sunday morning through 10 p.m. Monday.
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The California Independent System Operator (ISO) issued a heat bulletin Sunday in anticipation of increased electricity demand due to above normal temperatures across California. Potential for resource shortfalls are projected for Monday, but could be made up through voluntary consumer conservation.
If weather or system conditions worsen, the ISO may notify the public about potential energy shortages and the need to conserve. The ISO issued a flex alert for Monday, a voluntary call for consumers to reduce electricity use during critical times of stress on the grid, but it is no longer in effect, the ISO said.
Low daytime humidity levels in the arid eastern reaches of the county are expected to fall to around 10% through the weekend, forecasters said. Those conditions, combined with dry, gusty winds, will result in elevated wildfire hazards in the deserts and on the eastern slopes of the mountains.
For the early and middle part of next week, monsoonal moisture may begin to spread into the region, a development that could bring a chance of thunderstorms, mainly in the mountains and deserts and mostly during the afternoon and early evening hours, according to the weather service.
The potential for dry lightning strikes will be greater initially in the heat wave when atmospheric moisture will be relatively limited. The potential for rainfall may increase later in the week, meteorologists said.
San Diego County has opened the following cool zones for Sunday:
- The Borrego Springs Library, 2580 Country Club Road, open from 12 p.m. to 6 p.m.
- The Santa Ysabel Nature Center, 22135 Highway 79. open from 9 a.m. to 7 p.m.
Beating the Heat
Residents can cool down with air conditioners or fans, and those who want to go outdoors during the heat wave are encouraged to wear sunscreen. Everyone should remember to drink plenty of water in order to stay hydrated.
Heat-related illnesses such as heat exhaustion, heatstroke and heat cramps pose a threat during these times, especially to vulnerable communities like the elderly and children.
The Centers for Disease Control said such illnesses can be identified by symptoms that include fatigue, headache, cramping, dizziness, nausea, or vomiting and fainting. Anyone who sees someone in distress is urged to call 911 immediately.
It is also encouraged to refrain from leaving children and pets unattended in cars in order to prevent tragedy. Temperatures in an enclosed vehicle can skyrocket within just minutes, causing serious injury or even death.
The San Diego Humane Society offered some tips to keep pets cool in hot weather. Like providing plenty of water at all times, including when away from home, leaving pets inside where it's cool at home as much as possible and not leaving a pet alone in a parked vehicle -- even with the windows open.
