Washington, D.C., tied its Fourth of July record high Today as temperatures reached 100 degrees, matching a mark that had stood since 1919, even as a severe thunderstorm watch loomed over the region for later in the day. The heat dome responsible for the milestone has gripped the area for several days, and an Extreme Heat Warning remained in effect until 9 p.m., with heat index values expected to climb as high as 110 to 115 degrees when combined with high humidity.
The heat proved even more extreme at some regional airports. Reagan National Airport broke its own 1919 record with a high of 101 degrees, while BWI Marshall also hit 101, surpassing a previous record of 100 set in both 1898 and 1966. Dulles International Airport tied its own record high of 97 degrees, a mark last reached in 1999 and 2002. The extreme conditions also triggered a code purple air quality alert, meaning air quality was considered unhealthy for the general public, not just sensitive groups.
A severe storm threat adds a new complication
Beyond the heat, a Severe Thunderstorm Watch was issued for the D.C. region through 9 p.m. Today, with forecasters warning that the immediate metro area fell under an enhanced risk zone for dangerous storms. Meteorologists cautioned that any storms forming during the afternoon and evening could produce wind gusts between 70 and 80 mph, capable of downing trees and power lines and triggering scattered outages. Large hail, torrential rainfall and frequent lightning were also considered possible with the more intense storm cells.
Storm activity was expected to be most active during the mid to late afternoon hours before gradually diminishing by evening, offering a narrow window of improved conditions ahead of the National Mall fireworks display scheduled for around 10:30 p.m. Officials urged anyone attending outdoor events to remain weather aware and identify a safe location in advance in case warnings were issued during the celebration.
Holiday events reshaped by the weather
The extreme conditions forced organizers to cancel America’s Independence Day Parade in the district entirely, along with similar parades in Fairfax, Leesburg, Takoma Park and Laurel. The Salute to America celebration on the National Mall adjusted its schedule as well, delaying public entry to the Washington Monument viewing area until 5 p.m. in an effort to limit prolonged heat exposure for attendees…