The Summer cat title refers to the fact that many people abandon their pets (cats or dogs, usually) when the summer comes and they go on holidays. This songs talks about a man whose girlfriend leaves him after the holidays, probably because she's going back to her home.
Read this USEFUL VOCABULARY before you listen to the song:
Hold so close — abrazar tan fuerte
Wanna — want to
chilly wind —viento frío
whip —golpear (a veces también significa batir)
cheeks —mejilla
gonna —going to
wave my hand — mover la mano
Worn out hat — sombrero viejo
broken hearted —con el corazón roto
break into —entrar en un sitio por la fuerza (e.g. para robar)
whisper —susurrar
instead —en vez de (hoy)
clouds —nubes
naive —ingenuo
