Hi BBM2, Quarter Days were traditionally (and still are in certain financial transactions, particularly rent) due payment dates and an attempt to continue a financial theme. However, also an attempt to fine tune the definition because if you accept wiki's definition the difference between "normal" and flash flooding is the volume within a 6 hour period = 1/4 of 24 hours, 1 day.
I was very tempted by paul's "tidings" but BBM2 @ 9.
day's