L.A.’s muggy misery: Intense humidity makes summer heat even more unbearable
It’s not your imagination: This summer has been unusually sticky in Los Angeles, with humidity levels making conditions feel more like the Deep South than Southern California.
As summer heat settles over the Southwest, it changes the circulation in the atmosphere enough to pull up monsoonal moisture from the Pacific and Gulf of California, fueling warm rain and thunderstorms.
Exacerbating the conditions, the ocean water just off the coast has been unusually warm, with readings of 74 degrees off Hermosa Beach and 70 degrees off Zuma Beach as of Sunday, said Bryan Lewis, a National Weather Service meteorologist in Oxnard.
That means the afternoon sea breeze that typically helps cool down conditions, especially in coastal areas, is warmer. “It’s still cooling things down but not to the degree that we expect — and that our bodies expect,” Lewis said.
Players vie for the ball during a sunset basketball game at the Venice Beach courts.
(Genaro Molina / Los Angeles Times)
The protracted heat and humidity, with warm nights offering little relief, has had weather and public health authorities warning of an elevated risk of heat illness on and off for weeks. During the last two weeks, Los Angeles County has seen an increase in emergency visits for heat-related illness, according to a heat-related illness and mortality dashboard maintained by the county health department.
Conditions should cool slightly Tuesday through Thursday, with drier air sweeping in from the northwest to offer even more relief, according to the Weather Service, which does not expect to extend a heat advisory that expires at 8 p.m. Monday for many areas. Humidity levels will remain a bit above normal, especially for coastal areas, due to the warm ocean temperatures, Lewis said.
Still, the heat is expected to again increase Friday through Sunday, prompting more advisories later this week, Lewis said. The moisture will also likely return, with conditions feeling similar to the past three weeks or so, he said.
By Saturday, temperatures will be 10 to 15 degrees above normal, according to the Weather Service. Forecasters expect the valleys to reach 100 to 110 degrees, the lower mountain and far interior areas to reach 105 to 112 degrees and the beaches to be in the 80s. More heat advisories will almost certainly be in place.
Although it’s unclear to what extent climate change is influencing this particular heat wave, scientists have found that global warming from the burning of fossil fuels is making Western heat waves more frequent, persistent, humid and lethal.
Forecasters also continue to warn of dangerous rip currents and elevated surf of 3 to 6 feet across Los Angeles and Ventura County beaches. A beach hazard statement is in effect through Wednesday afternoon.
