Heat-Related Emergency Department Visits During the Northwestern Heat Wave - United States, June 2021

Record high temperatures are occurring more frequently in the United States, and climate change is causing heat waves to become more intense (1), directly impacting human health, including heat-related illnesses and deaths. On average, approximately 700 heat-related deaths occur in the United States each year (2). In the northwestern United States, increasing temperatures are projected to cause significant adverse health effects in the coming years (3). During June 25-30, 2021, most of Oregon and Washington were under a National Weather Service excessive heat warning.* Hot conditions persisted in parts of Oregon, Washington, or Idaho through at least July 14, 2021. The record-breaking heat had the largest impact in Oregon and Washington, especially the Portland metropolitan area, with temperatures reaching 116°F (46.7°C), which is 42°F (5.6°C) hotter than the average daily maximum June temperature.