What to Know
- An excessive heat warning for the deserts is in effect until Friday at 9 p.m. and the mountains and valleys until 9 p.m. Thursday
- Temperature records were broken in Ramona and Campo on Tuesday
- The county will also have elevated fire danger due to the hot and dry weather
San Diego's coastline is the only area to escape the National Weather Service's excessive heat warning as temperatures soar close to 100 degrees or more for the rest of the county.
"For the coast, we will be warm but it will be the coolest place in the county -- close to 80 degrees," NBC 7 Meteorologist Sheena Parveen said. "Most of our inland valleys will be in the low-90s but it's closer to the foothills and the mountains that will be hottest."
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The excessive heat warning was already in effect for the mountains and deserts but also overtook the inland valleys late Tuesday morning.
Temperatures inland range from 92 to 98 degrees this week and could enter triple-digit territory in the foothills, Parveen said, adding that it's possible some areas could reach near-records.
The heat warnings will expire 9 p.m. Thursday for the mountains and valleys and at 9 p.m. Friday for the deserts.
Local
For San Diego County, the hottest days of the week county-wide were expected Tuesday and Wednesday.
"Wednesday will be as hot, if not hotter," NBC 7 Meteorologist Greg Bledsoe said. "Wednesday could end up being the hottest day of the week during this heat wave."
Wednesday's First Alert Weather forecast:
- Coasts: Gradual clearing, 78
- Valleys: Heat warning, 93
- Mountains: Heat warning, 98
- Deserts: Dangerous heat, 119
The conditions continue a lengthy heat wave that began ahead of the Fourth of July holiday and had affected most of the Western U.S. as a dome of high pressure lingers from the west.
Global temperature in June was record warm for the 13th straight month and it marked the 12th straight month that the world was 1.5 degrees Celsius (2.7 degrees Fahrenheit) warmer than pre-industrial times, the European climate service Copernicus said.
The extreme heat can be deadly and already resulted to the death of a motorcyclist and severe heat-related illness of another, who were in Death Valley as temperatures soared to 128 degrees.
San Diego County's desert, Borrego, reached a new record high with 120 degrees on Monday, beating it's 1976 record of 117 for that day of the year. Big Bear, Idyllwild, Palm Springs and Indio also beat or tied previous records.
On Tuesday, highest maximum temperature records were broken in Ramona and Campo and tied in San Jacinto, according to the NWS.
More historic records could be made in the coming days.
The county will also have elevated fire danger due to the hot and dry weather.
A slow cooling trend is expected to begin on Friday.
"We're going to decrease about a degree or two each day as we head into the weekend, so don't expect a sudden drop off of these temperatures," Bledsoe said.
Besides the slight cooldown, it will be more humid later in the week.
"We have some monsoonal moisture on the way. That will bring a chance for some mountain showers or thunderstorms, possibly deserts as well," Bledsoe said.
Heat safety tips
- Avoid the sun from 11 a.m. to 2 p.m., when the UV Index could be 11+
- Stay cool by taking breaks in the shade and the AC
- Wear SPF 30+ and lightweight or light-colored clothes outdoors
- Stay hydrated by drinking 8 oz. of water every 15-20 minutes
Heat-related illness is no joke. The County of San Diego is stressing caution and awareness of heat exhaustion and heat stroke.
Officials advised people to "drink plenty of fluids, stay in an air- conditioned room, stay out of the sun and check up on relatives and neighbors."
Never leave children or pets unattended in vehicles. Officials warn vehicles can reach lethal temperatures in minutes.
Heat warnings also apply to furry companions as well. San Diego County officials advised residents to keep their pets indoors, so long as the temperature is lower inside. People should also:
- exercise animals in early morning or evening to avoid prolonged exposure to the heat, and also skip strenuous runs or hikes
- keep pets' water supply in a tip-proof container, and make sure the dish always topped off and stays cool (as pets won't drink water that is too hot)
- if possible, install a misting system to keep outdoor areas cooler
- be sure animals, if they are outside, are constantly in a shaded area
- avoid taking pets on car trips without air-conditioning unless necessary, as a vehicle can quickly heat up (on an 85-degree day, a car can reach 102 degrees in 10 minutes, even with the windows down)
- avoid walking dogs on hot pavement
- allow dogs to use a child's wading pool
Below are the signs of heat exhaustion and heat stroke:
