California June 15, 2021 6:57 am What Defines a Heat Wave? We often hear about “heat waves” in San Diego County but what, exactly, defines this weather pattern? NBC 7 meteorologist Dagmar Midcap explains. US & World Videos 2:39 Doctor thanks San Diego first responders who saved his life after bike crash 1:00 Shooting investigation underway on Mission Bay's Fiesta Island 2:05 San Diego weather today: Brooke Martell's morning forecast for Oct. 2, 2024 4:14 Free ride day Wednesday on Trolleys, buses, Coaster and Sprinter 2:08 Fans pack the East Village after Padres beat Braves in playoff opener