The California heat wave has persisted for a week and shows no signs of letting up until the interior sees relief next weekend. By then, many inland areas will have been under some form of heat alert for over nine days.

The National Weather Service has described the situation as a “seemingly endless heat wave,” with warnings in place for much of the state’s interior until Saturday. In some cases, the heat has already proven deadly, prompting authorities to urge the public to take extreme heat seriously.

The duration and intensity of this heat wave have been repeatedly described as unprecedented, breaking numerous high-temperature records in the Golden State and the western U.S.

California heat wave breaks all-time high temperature records

From July 1 to July 7, Redding experienced an astonishing average daily high temperature of 112.6 degrees, with five consecutive days reaching at least 110 degrees.

The intense early-season heat wave sweeping across much of the western U.S. has already shattered numerous records and caused several deaths, but it’s far from over. This situation is expected to persist for another week, with triple-digit temperatures exacerbating health issues and wildfire risks in California and neighboring states.

In Bakersfield, temperatures haven’t dropped below 80 degrees since the 4th of July. Meanwhile, Sacramento’s daily average temperature, calculated from daily highs and lows, has been 87 degrees since the start of the month, 11 degrees above normal, marking the hottest start to July on record for the city.

One reason this heat wave has been so prolonged and relentless is that the heat dome responsible for the record-breaking temperatures originated over the Pacific Ocean early in the month. It gradually moved eastward over the state’s interior, fluctuating slightly in strength and resulting in two significant peaks in high temperatures around the holiday and again over the weekend, when most temperature records were set.

The impacts have been widespread across California’s diverse microclimates. This heat wave is expected to have one final surge of strength starting Wednesday and lasting through the end of the week, with relief anticipated over the weekend after nearly two weeks of persistent heat.