Northern California was under a rare and brief tsunami warning alert Thursday that tested local emergency notification systems after a 7.0 magnitude earthquake shook part of the state.
The National Weather Service canceled its alert after roughly an hour and before the tsunami was expected to arrive. In that hour, some cities and counties ordered evacuations while others relied on social media and text messages to inform people of the warning. Some people headed for higher ground, while others drove to the beach to get a better view.
