The External Solemnity of Corpus Christi may be held in USA (White).
There is no commemoration of the Vigil of the Nativity of St. John the Baptist, nor is there a commemoration of the Sunday in Masses of the External Solemnity (same Person).
The Corpus Christi procession may be held today with the External Solemnity. The Blessed Sacrament is processed under a canopy. Additional altars of repose may be used along the procession route, with Benediction given there. (In hot regions the altars of repose are often deferred until the procession of Christ the King in October.) The final Benediction is given upon return to the church. The procession route should be decorated if possible; frequently carpets are fashioned out of flower petals or colored sawdust arranged in devotional designs. If the procession cannot be held outdoors, it may be held around the interior perimeter of the church.
External Solemnity: Mass of Corpus Christi (White); Gloria; no commemoration of Sunday; Sequence Lauda Sion, Credo; preface of the season (Holy Trinity).
In the Mass preceding the Procession, a second Host is consecrated and exposed in the Monstrance after Communion and before the ablutions. The remainder of the Mass continues coram Sanctissimo. Benedicamus Domino is said and the Last Gospel omitted, before the Procession departs.
Other Masses: Mass of the Sunday (Green), Gloria, Credo, preface of the Holy Trinity
Matins: Invitatorium and Hymn per annum as given in the psalter; three lessons proper; Te Deum
Lauds: Antiphons and psalms of Sunday (first schema); remainder per annum as given in the psalter; Benedictus antiphon and oration proper
Hours: Antiphons and psalms of Sunday (at Prime, Psalm 117 is used); remainder per annum as given in the psalter; oration proper
I Vespers: Of the Nativity of St. John the Baptist; proper antiphons, with Sunday psalms except for Psalm 116 as the fifth psalm; remainder proper; commemoration of the II Sunday after Pentecost
Compline: Of Sunday
This evening (Vigil of St. John the Baptist) bonfires are traditionally made, which receive a special blessing as given in the Rituale (De Benedictionibus, no. 10: Benedictio Rogi quae fit a clero extra ecclesiam in Vigilia Nativitatis S. Joannis Baptistae):
V. Adiutorium nostrum in nomine Domini. R. Qui fecit caelum et terram.
V. Dominus vobiscum. R. Et cum spiritu tuo.
Oremus. Domine Deus, Pater omnipotens, lumen indeficiens, qui es conditor omnium luminum: novum hunc ignem sancti + fica, et praesta; ut ad te, qui es lumen indeficiens, puris mentibus post hujus saeculi caliginem pervenire valeamus. Per Christum Dominum nostrum.
Et aspergatur aqua benedicta. Deinde a Clero cantetur Hymnus Ut queant laxis e I Vesperis, et sequuntur versus et oratio earundem Vesperis.