This is the link to the Kindle/comiXology English digital version ($6.99). It's Volume 1 and ends with Mitsuha watching the comet at the festival, and Taki on the bridge reading Mitsuha's text about watching the comet later that night.
The manga is quite good with, among many other things, many of the phone texts, written notes, and notes on arms, hands and cheeks, between Taki and Mitsuha in English that were not subtitled in Funimation's theatrical release. Quite humorous stuff!
Volume 2 of the English manga will be released November 14, 2017.