09/30/2025 | Press release | Distributed by Public on 09/30/2025 07:38
What GAO Found
Between 2018 and 2024, 97 percent of counties across the contiguous U.S. were projected to reach at least level 3, a dangerous level of heat, by the National Weather Services's HeatRisk, a 5-level index for potential heat-related effects. In addition, more than 319 million people lived under a forecast that was at a dangerous level for at least one day during this period of time.
Average Days per Year at HeatRisk Level 3 and Above by County, 2018-2024
FEMA has provided limited assistance to tribal, state, and local governments for projects to mitigate against extreme heat. For example, less than 1 percent of the agency's Building Resilient Infrastructure Communities (BRIC) 1,235 grant projects with obligations from fiscal years 2020 through 2023 primarily addressed extreme heat.
Further, there has never been a presidentially declared major disaster for an extreme heat event, which would trigger federal assistance, such as damaged infrastructure, emergency protective measures for survivors, and mitigation assistance. According to FEMA, past extreme heat events have caused little infrastructure damage, a key criterion for approving federal assistance. FEMA officials told us that absent extraordinary circumstances, it was unlikely that a president would ever declare a major disaster for extreme heat. Agency officials reported providing some assistance for extreme heat when responding to other approved disasters, such as distributing commodities to Houston, Texas after Hurricane Beryl.
However, FEMA has not evaluated its role in helping tribal, state, and local governments to plan for and implement activities that reduce or mitigate future disaster losses from extreme heat events. Moreover, FEMA has also not assessed how its potential decision to end BRIC may affect the agency's ability to assist these entities. Evaluating FEMA's role and its capabilities for assisting tribal, state, and local governments to prepare, respond, and recover from extreme heat events would help the agency to fully identify any gaps in assisting these governments and determine how to best address them. The evaluation's results could also be incorporated into any upcoming changes to FEMA's role or reform efforts.
Why GAO Did This Study
According to the National Weather Service, extreme heat is the leading weather-related cause of death in the U.S.-killing more people than floods, hurricanes, and tornadoes combined. These events are forecast to grow in intensity, frequency, and duration.
GAO was asked to examine the Federal Emergency Management Agency's (FEMA) support for states and localities experiencing extreme heat events. This report examines (1) where forecast data projected extreme heat could occur; (2) the extent FEMA assisted Tribes, states, and localities to mitigate extreme heat; and (3) the extent that FEMA helped these entities respond to and recover from extreme heat events.
GAO reviewed FEMA documentation; analyzed heat index data from January 2018 through October 2024 and FEMA grant data from fiscal years 2020 through 2023; interviewed emergency management or public health officials, subject matter experts; and FEMA officials.