"...coming up ... 'Witching Hour, with the popular singing sorceress, Celestina Warbeck.'"
-- announcement on the Wizard Wireless (CS3)
A popular show on the Wizard’s Wireless hosted by Glenda Chittock (FW).
Harry heard an announcement for the show featuring singer Celestina Warbeck on the old radio at the Burrow in Molly Weasley's kitchen (CS3).
Witching Hour traditionally means the hours after midnight when witches were thought to be most powerful and up to their tricks. But the phrase has come to be used in other ways to denote bad luck or the unexpected, such as the late afternoon hours when stock markets rise and fall precipitously. Of course, in Harry's world every hour is Witching Hour, so the wireless show is turned on in the morning at the Burrow.