Grimshaw’s earliest influence was the Pre-Raphaelites. True to the Pre-Raphaelite style, he created landscapes of accurate colour and lighting, vivid detail and realism, often typifying seasons or a type of weather. Moonlit viewsofcity and suburban streets and of the docks in London, Leeds, Liverpool and Glasgow also figured largely in his art. The focus on atmosphere, and lack of moral message or historical reference allies his work to some extent with the Aesthetic Movement.
His careful painting and his skill in lighting effects meant that he captured both the appearance and the mood of a scene in minute detail. His “paintings of dampened gas-lit streets and misty waterfronts conveyed an eerie warmth as well as alienation in the urban scene.” Later in life his colour palette shifted from dark blues to golden yellows, and towards the end of his life were hints of a change in artistic direction, with looser brushwork influenced by his friend James Abbott McNeill Whistler, who was quoted saying “I considered myself the inventor of Nocturnes until I saw Grimmy’s moonlit pictures.”