February 2, when a Pennsylvania groundhog predicts six more weeks of winter, a ritual imported and adapted twice.
Documented
The Candlemas chain
Candlemas, February 2, carried European weather lore: sun that day meant more winter. German farmers watched the badger on Dachstag; the Pennsylvania Dutch swapped in the local groundhog, dox in their dialect, and stretched the penalty from four weeks to six. The earliest US mention is James Morris's diary, February 2, 1840. Punxsutawney made it official in 1887.
Assessment: Documented: diaries, dialect records, and the German farmer rhymes all survive.
Stories
The Scots couplet
Under the animal layer sits a simpler rule in a Scots rhyme: if Candlemas is fair and clear, there'll be twa winters in the year. A Latin version exists too, which some take as proof the lore is ancient.
Assessment: Stories: the rhyme is real, its age is guesswork.
Interesting claims
The hedgehog rumor
Popular books from 1886 and 1900 claimed British Romans watched hedgehogs for the same omen, implying an unbroken pagan line. Scholar Rhys Carpenter checked in 1946: the badger tradition is strong in Germany and absent in the British Isles; the hedgehog claim has no demonstrated age.
Assessment: Interesting claims: repeated for a century, evidenced never.
Sources and further reading
James L. Morris diary entry, February 2, 1840, Morgantown, Pennsylvania, via Don Yoder, Groundhog Day (2003)
Austrian Bauernregeln collection (1823): if the badger suns at Candlemas, four more weeks in his hole
The Thomas R. Brendle Collection of Pennsylvania German Folklore: Grund'sau dåk shadow lore
Punxsutawney Spirit records of the first official Groundhog Day, 1887
Rhys Carpenter (1946): the badger tradition is German, absent in the British Isles; the hedgehog claim undemonstrated
Worth asking
America trusts its weather to a stand-in for a stand-in; what other authorities started as whoever was available?