San Diego is getting more heat streaks on average each year than in 1970, a new analysis shows.
Why it matters: Extreme heat is particularly hazardous to human health, and air conditioning is less common in San Diego than in warmer climates.
- Extreme heat’s effects on the body tend to be cumulative, and warm nights offer little reprieve for those without air conditioning.
- Multi-day heat streaks are also challenging for power grid operators, given all the energy-intensive A/C use.
By the numbers: The average number of annual extreme heat streaks rose between 1970-2024 in 80% of the 247 U.S. cities analyzed in a new report from Climate Central, a climate research group.
- San Diego now has on average two more heat streaks each year, in line with the 200 cities in which heat streaks became more common.
How it works: Climate Central defines an “extreme heat streak” as three or more days in a row with maximum temperatures over the 90th percentile of a given location’s daily max temperatures during the 1991-2020 period…