(BCN) -- The Bay Area Air Quality Management District said a fifth-straight Spare the Air alert will be in effect for Saturday due to an extended heat wave that is leading to unhealthy levels of smog in the region. The heat wave peaked Wednesday with temperatures at about 110 degrees in some inland parts of the Bay Area but will still be in the upper 90s to low 100s Saturday, according to the National Weather Service. Red Flag Warning issued for parts of Bay Area The hot weather, combined with weak winds and exhaust from motor vehicles is creating elevated concentrations of smog, otherwise known as ozone, according to the air district. Smog can cause throat irritation, chest pain or other problems and is particularly harmful for young children, seniors and people with respiratory or heart conditions. On Spare the Air days, people are encouraged to only exercise outdoors in the early morning hours when smog levels are lower. People can find out when a Spare the Air alert is in effect by visiting www.sparetheair.org, calling (800) HELP-AIR, downloading the Spare the Air app on their smartphone or find Spare the Air on social media. Copyright © 2024 Bay City News, Inc.