The Birth of St. John the Baptist is a solemnity, and so observance still begins with Evening Prayer I in the Liturgy of the Hours of the preceding day. The liturgical day is from midnight to midnight in the Church’s observance, except for Sunday and solemnities which begin with the evening of the preceding day. According to the 1962 Missal of St. John XXIII the Extraordinary Form of the Roman Rite, today is the Vigil of St. John the Baptist.