Washington, D.C. — A dangerous wave of extreme heat is set to engulf the D.C. metro area and surrounding regions on Friday, July 25, with heat index values soaring as high as 109°F, according to the National Weather Service (NWS) in Baltimore/Washington.
A Heat Advisory has been issued for much of the Mid-Atlantic region, taking effect from 11 a.m. to 8 p.m. on Friday. The advisory spans nearly 30 counties, including all of Washington, D.C., the Baltimore metro, Northern Virginia, and parts of the Eastern Panhandle of West Virginia.
“With this level of heat and humidity, the risk of heat-related illness significantly increases—especially for young children, the elderly, and those with pre-existing health conditions,” said a statement from NWS Baltimore/Washington.
Heat Index Forecasts by Region:
- Washington, D.C. & Baltimore: Up to 109°F
- Northern Virginia (Frederick, Arlington, Manassas): Around 105°F
- Maryland (Annapolis, Frederick, Prince George’s County): Between 103–108°F
- Eastern Panhandle of West Virginia (Berkeley, Jefferson Counties): Around 103°F
- Shenandoah Valley (VA): Mid-100s expected
Cities directly impacted by the advisory include Washington, Baltimore, Arlington, Frederick (MD & VA), Annapolis, Manassas, and Winchester.
Health Risks and Safety Precautions
Officials warn that this level of heat can trigger heat exhaustion, heat stroke, and other serious health problems. Vulnerable groups—such as older adults, infants, outdoor workers, and people with chronic conditions—are most at risk.
Residents are urged to:
- Stay indoors during peak heating hours (11 a.m.–8 p.m.)
- Drink plenty of water, even if not thirsty
- Avoid strenuous outdoor activity, or shift it to early morning/evening
- Wear light-colored, loose-fitting clothing
- Use air conditioning or visit public cooling centers like libraries and shopping malls
- Check on neighbors, particularly elderly or medically fragile individuals
Importantly, never leave children or pets in vehicles, even for a short time. Interior car temperatures can become deadly in minutes under extreme heat.
Read Also: Maine Weekend Forecast: Rain Friday, Temps Near 80°F, More Storms Ahead
More Heat on the Horizon?
This marks the most intense heat wave of the summer so far for the D.C. area. The NWS warns that conditions could persist or worsen into the weekend, and additional heat advisories or warnings may be issued depending on how the weather evolves.
Residents are advised to monitor local forecasts, sign up for emergency weather alerts, and prepare for possible air quality impacts or power grid stress as demand for cooling increases.
For updates and a list of active cooling centers in your area, check with your local emergency management office or visit weather.gov.
