For those who don't know, Imbolc--falling roughly halfway between the winter solstice and spring equinox (or, Christmas and Easter)--is the old Irish start of spring; it's a feast of purification1, and comes a day after the feast of Brigit, the goddess and the saint. In the Catholic calendar, it's also Candlemas/the Feast of the Purification of Mary. But you probably know it best as Groundhog Day.
Using this day for prognosticating the future weather goes way back, certainly long before some Pennsylvanian marmot chewed his way out of the ground. Plus, before him, it used to be a snake. To read a good summary of how Brigit relates to spring and predicting the weather in February, check out Alexander Carmichael's classic Carmina Gadelica:
The serpent is supposed to emerge from its hollow among the hills on St Bride's Day, and a propitiatory hymn was sung to it. Only one verse of this hymn has been obtained, apparently the first. It differs in different localities:--
'Moch maduinn Bhride,
Thig an nimhir as an toll,
Cha bhoin mise ris an nimhir,
Cha bhoin an nimhir rium.'
Early on Bride's morn
The serpent shall come from the hole,
I will not molest the serpent,
Nor will the serpent molest me.
Other versions say:--
La Feill na Bride,
Thig nighean Imhir as a chnoc,
Cha bhean mise do nighean
’S cha dean i mo lochd.' [Imhir,
'La Fheill Bride brisgeanach
Thig an ceann de in chaiteanach,
Thig nighean Iomhair as an tom
Le fonn feadalaich.'
'Thig an nathair as an toll
La donn Bride,
Ged robh tri traighean dh’ an
Air leachd an lair.' [t-sneachd
The Feast Day of the Bride,
The daughter of Ivor shall come from the knoll,
I will not touch the daughter of Ivor,
Nor shall she harm me.
On the Feast Day of Bride,
The head will come off the 'caiteanach,'
The daughter of Ivor will come from the knoll
With tuneful whistling.
The serpent will come from the hole
On the brown Day of Bride,
Though there should be three feet of snow
On the flat surface of the ground.
The 'daughter of Ivor' is the serpent; and it is said that the serpent will not sting a descendant of Ivor, he having made 'tabhar agus tuis,' offering and incense, to it, thereby securing immunity from its sting for himself and his seed for ever.
In America, the day has become associated with the 1993 movie Groundhog Day. In one of those wonderful cosmic convergences, the theme of the movie actually fits the original theme of the holiday: Phil Connors, the miserable, venal weatherman played by Bill Murray, spends lifetimes living the same day over and over again, indulging in every vice you can find in a small Pennsylvania town, before slowly learning to become a better person. What's funny, of course, is that the origin of Imbolc--like the Roman Lupercalia, or the Catholic Lent--is in a time of purification. Like Phil, we're all living the same day over and over again; sometimes we waste our time, which is easy, especially in winter when we're miserable. But hey, unlike Phil, we don't have an eternity to get it right. We invent times like Imbolc to get ourselves back on track, to remind ourselves that winter doesn't last forever, that spring is coming, and we need to get our heads together. To purify ourselves, to make ourselves better people.
Hey--the groundhog called for an early spring. Better get crackin'.
1. Eric Hamp, 'Imbolc, Oimelc', Studia Celtica, 14/15 (1979/1980)