Southern California is bracing itself for another bout of sweltering heat, as temperatures are set to soar into the triple digits in certain areas. The National Weather Service has issued heat advisories across the region, anticipating the hottest days to be Wednesday and Thursday.
These advisories will remain in effect until 8 p.m. Friday, affecting various areas differently. In Los Angeles County, interior valleys and mountainous regions might experience temperatures reaching 105 degrees, while inland coastal areas like downtown L.A. are expected to see highs in the low 90s. Coastal regions will enjoy slightly cooler temperatures in the 70s and 80s.
The forecast
Orange County: This area will experience milder heat, with inland temperatures in the 80s and coastal areas remaining in the 70s.
Inland Empire: The valleys of Riverside and San Bernardino Counties could reach the low 100s, with the mountains expected to hit the mid-90s.
Coachella Valley: A more severe Extreme Heat Warning has been announced, with temperatures potentially climbing to 116 degrees. Nighttime lows will remain warm, dipping only to the 80s.
Such elevated temperatures pose significant health risks, particularly for vulnerable groups like the elderly, young children, and those with pre-existing health conditions.
What’s driving the high temperatures?
The current heatwave is primarily driven by a high-pressure system and off-shore winds, known as Santa Ana winds. According to Lisa Phillips, a National Weather Service meteorologist in Oxnard, “Everything is dictated by which way your winds are blowing and high-pressure systems.” These systems push warm air down towards the ground, while the winds bring hot, dry air from inland deserts to the coast, intensifying the heat in the L.A. basin.
This heatwave coincides with the weakening of the marine layer, a cooler air mass that usually provides some relief during late spring and early summer. As summer progresses, this marine layer retreats, resulting in higher temperatures.
Fire risk
The combination of high temperatures and dry conditions has heightened the risk of wildfires, especially in valleys, foothills, and mountainous areas. Phillips advises residents to exercise caution, as the dry vegetation becomes easily flammable. “We are headed into our fire weather season, where we have more wildfires. The vegetation is dry, so it does catch fire more easily,” she explained, noting the increased fire danger in Southern Santa Barbara County due to gusty winds.
What’s next?
A slight cooling trend is expected to begin Friday as the high-pressure system moves eastward, allowing for some moisture to bring cooler temperatures. However, temperatures will remain above average through the weekend, with another potentially more severe heatwave anticipated shortly thereafter. “We could be looking at even warmer temperatures next week,” Phillips warned.
Original Story at laist.com