The heat wave that began Friday in California could rival the deadly seven-day heatwave of July 2006, the National Weather Service said.
The valleys, mountains, and deserts of southern California are likely to surpass daytime and nighttime temperatures over records at least through Thursday, and humidity will make conditions 2 to 5 degrees warmer during the day.
Extensive views prepared by the National Oceanic and Atmospheric Administration favor above-normal temperatures that persist well above Thursday.
The excessive heat is the result of a large, strong high-pressure system centrally located across Arizona that keeps the Southwestern US hot almost everywhere except within a few miles of the coast.
High pressure over southwestern California on Tuesday will reach a strength that only occurs about every 10 years, said Eric Boldt, a meteorologist with the National Weather Service in Oxnard. This high-pressure air dome blocks storm systems and creates building whites across the Southwest.
It was during the deadly heatwave of 2006 that Los Angeles County recorded its worst temperature of all time: 119 degrees in Woodland Hills on July 22nd.
The Times reported that wreaths in Los Angeles, San Bernardino and Kern counties linked about 130 deaths to the heat, with diagnoses including hyperthermia and heat stroke. But state researchers later estimated that tolls in those counties were more likely to range from 350 to 450.
This time, California is sinking into the statewide heatwave with the ongoing COVID-19 pandemic as a sort of precautionary measure.
The National Water Service warned Friday of the very real potential for heat stress and heatstroke with the current heat wave.
Valleys in the Los Angeles area can expect heights of 100 to 108 degrees, with lows of 72 to 82. Heights below 5,000 feet will show heights of 98 to 105 and lows of 65 to 75 degrees. High temperatures will be 102 to 112 in the Antelope Valley, with lows of 70 to 80. Coastal areas can look for heights of 82 to 92 and lows of 65 to 70.
Critical heat will occur between the hours of 11 a.m. and 7 p.m. daily, especially inland, the weather service said. Night temperatures do not cool enough to provide comfortable sleeping water in many places.
Short elevated to critical fire water conditions will exist daily during the period, with concerns about the possibility of new fire starts from isolated dry lightning streaks. Plume-dominated fires can lead to rapid fire spread and locally unpredictable winds.
There is a chance of thunderstorms Saturday, and again Sunday through Tuesday, when it is expected that morning will return. Even if it’s not raining where you are, the humidity will likely cause the kind of unusual harsh conditions with which Californians are largely unfamiliar. Heavy rain and flash floods could have accompanied any thunder activity.
Above normal temperatures in the Western US have contributed to the expansion of drought conditions.
(Paul Duginski / Los Angeles Times)
Monsoon rains in the Southwest have remained disappointingly spotty at best, according to the most recent US D Dry Monitor report, released Thursday. Some parts of the Southwest expect to receive half of their rainfall during the North American monsoon. Parts of Arizona and New Mexico maintained temperatures that were 3 to 5 degrees above normal during the last week.
Although drought conditions in California remained about the same, extreme drought in the West expanded by nearly 1.4%. Areas of the West that are considered a moderate drought grew by 1.3%, and areas of severe drought increased by nearly 1%, according to data from the U.S. Drought Monitor.
