Not exactly...
Halloween (Hallow E’ning) is the Eve of All Hallow’s/All Saint’s day.
Valentine was on the Roman Catholic calendar until calendar reforms in the wake of Vatican II and he continues to be listed on the Orthodox calendar.
St. Patrick is on the calendars of all the liturgical churches (Catholic, Anglican, Lutheran, Orthodox) and, remarkably, all commemorate him on the same day—March 17.
Groundhog Day—the marmot co-opted the Christian Feast of the Presentation of Our Lord in the Temple (and the Purification of the Blessed Virgin Mary), again universally celebrate by the liturgical churches 40 days after Christmas.
Groundhog day is an observance—Candlemass is a Holyday.