Napa, Calif., quake disrupted Bay Area sleep patterns, fitness bracelets show

Data from Jawbone show many users were jolted awake by the 6.0-magnitude earthquake that struck the Bay Area early Sunday morning.

The 6.0-magnitude earthquake that hit Northern California at 3:20 a.m. Sunday damaged homes, buckled roads and sent more than 170 people to the hospital.

It also jolted many Bay Area residents awake in the middle of the night.

By examining data from thousands of users who wear fitness- and sleep-tracking bracelets to bed, the San Francisco technology company Jawbone has attempted to quantify just how many Bay Area residents lost sleep on Sunday.

According to company data released Monday, about 93% of Jawbone wearers in a 15-mile radius from the quake’s epicenter, including residents of Napa and Sonoma, were jolted awake. About 45% of those people stayed up the rest of the night, the company said.


Moving farther from the epicenter, about 74% of users who lived closer than 25 miles to the epicenter woke up, including Berkeley and Vallejo residents.

In San Francisco and Oakland, about 55% of users were awake directly after the earthquake -- a 41-percentage-point increase from a half-hour earlier. About three-quarters of those people had fallen back asleep by 5:30 a.m., the data indicate.

Analysts saw only a small spike in users who woke up in Sacramento and San Jose. About 11% of users were awake at 3 a.m., which jumped to 25% when the earthquake hit. An hour later, sleep patterns had settled back to pre-earthquake levels.

In Modesto and Santa Cruz, more than 75 miles from the epicenter, it appeared that almost no users woke up.

“We wish all the people in the Bay Area who were affected by the earthquake a speedy recovery and a good night’s sleep,” data analyst Brian Wilt wrote on Jawbone’s blog.

Jawbone’s full interactive graphic can be found here.

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