a_t_rain

If you want to leave the snarky dialogue in, you can either have a conversation by Patroni, portraits, another remote-communication device (maybe they really do have Instant Message books), or have Snape go to Grimmauld Place in person, by Apparating or flying. (It would be funny if he went looking for Harry, saw the missing Thestrals, realized that Harry had gone after Sirius, and took another one to Grimmauld Place.) (I suppose that he could also take the Knight Bus. I can't see why, but he could.)