Historical clue formulations

• Annual river thawing — 2024-11-10
• Rapid breakup of a frozen stream in the spring — 2019-12-18
• Spring river breakup — 2018-04-15
• Spring river breakup — 2014-03-16
• Post-winter breakup — 2012-12-22
• Annual river thaw — 2009-05-15
• Spring river breakup — 2008-07-04
• Spring river phenomenon — 2007-09-21
• Postwinter flood — 2005-01-30
• Rapid river thaw — 1999-07-17