What is the song dog days are over about?

What is the song dog days are over about?
"Dog Days Are Over" was recorded with no instruments in a studio the "size of a loo". The song was inspired by a giant text installment titled "Dog Days Are Over" by artist Ugo Rondinone, which Welch used to see every day, riding her bike over Waterloo Bridge. The song was produced and mixed by James Ford of Simian Mobile Disco and The Last Shadow Puppets, who is also famous for producing for the likes of Bloc Party and the Arctic Monkeys. He is also credited as playing piano and guitar on the record. Florence co-wrote the song with Isabella Summers who is also credited as the song's co-producer, and played piano on the record. Welch and Summers also teamed up for the percussion on the track, together with Charlie Hugall. "Dog Days Are Over" also features musicians Tom "Moth" Monger (harp), Bruce White (viola), Everton Nelson (violin), Christopher Lloyd Hayden (drums) and Rob Ackroyd (guitar). Jimmy Robertson, extensively involved in the recording of Lungs recorded and mixed "Dog Days Are Over" as well