After commissioning, "Tempest" joined the Tenth Destroyer Flotilla as part of the Harwich Force in April 1917. On 23 April 1918, "Tempest" participated in the First Ostend Raid, for which she formed part of "Unit X" which sailed from Dover and escorted the blockships from the Goodwin Sands until they reached a smoke screen which had been laid by Motor Launches off Ostend. After that they joined the Dunkirk-based destroyer flotilla in supporting the small craft inshore, "within close range of the enemy's heavy batteries". "Tempest" remained with the Tenth Flotilla at Harwich until its dispersal in February 1919. In October 1919, she was recommissioned with a reduced complement.