U.S. flags are traditionally flown at half-staff until noon on Memorial Day.
Under the U.S. Flag Code, the flag is displayed at half-staff from sunrise until noon on Memorial Day. It is then raised to the top of the staff until sunset. The two-part display symbolizes mourning for the nation’s war dead during the morning and the resolve to continue living for the country during the afternoon.
This practice is separate from the National Moment of Remembrance, which occurs at 3 p.m. local time. The flag’s noon change and the 3 p.m. pause are therefore different Memorial Day observances.
Half-staff is the usual term for flags on land; half-mast is commonly used for flags on ships. The President, governors, and other authorities may also order special half-staff periods after national tragedies or the deaths of officials.