13 Æfterra Gēola is se þrēotēoða dæg þæs gēares in þǣre Gregoriscan gerīmbēc. Heonan sind 352 belīfendra daga (353 in hlīepgēarum). Hē is Nīwes Gēares Ǣfen in þǣre Iuliscan gerīmbēc.