Ice Out Dates, Lake Iroquois

 YEAR     DATE
 1987  April 9
 1993  April 17
 1994      April 24
 1995  March 27
 1996  April 7
 1997  April 10
 1998  April 8
 1999  April 4
 2000  March 9
 2001  April 24
 2002  April 1
 2003  April 17
 2004  April 15-16
 2005  April 10
 2006  April 1
 2007  April 27
 2008  April 12
 2009  April 2
 2010  April 2
 2011  April 16
 2012  March 17-18
 2013  April 7
 2014  April 19
 2015  April 19
 2016  March 17
 2017  April 10


 Day   Year  Year  Year
 March 9  2000    
 Mach 17-18
 2012  2016  
 April 1  2002  2006  
 April 2  2009  2010  
 April 3      
 April 4  1999    
 April 5      
 April 6      
 April 7  1996  2013  
 April 8  1998    
 April 9  1987    
 April 10  1997  2005  2017
 April 11      
 April 12      
 April 13  2008    
 April 14      
 April 15  2004    
 April 16  2011    
 April 17  1993  2003
 
 April 18      
 April 19  2014  2015  
 April 20      
 April 21      
 April 22  1995    
 April 23      
 April 24  1994  2001  
 April 25      
 April 26      
 April 27  2007    

Ice out dates are courtesy of Betty Lantman and Davey DeGraff.  
If you have any dates that we've missed, let us know.


Notes on Lake Freezing and Thawing

Water is most dense at 4 degrees Celsius.

In the Spring, as the temperature of the air rises, the temperature of the surface of the ice rises. When the water at the top surface of the ice reaches 4 degrees C., it becomes more dense and it sinks, mixing with the water under the ice. Warmer water rises ("mixing" occurs, or as we used to say, " The lake is working"), as warmer water, with nutrients and material from the bottom of the lake, moves upward. As the surface of the ice melts further, the entire sheet of ice reaches above 0 degrees, and the ice "suddenly" disappears ("ice out"). 

In the Fall, air temperatures fall, and water on the surface of the lake cools (as we all know!). When the water reaches 4 degrees C. it sinks, and warmer water comes to the surface, to be cooled further (The lake has been "working" again) . When the water at the surface finally reaches 0 degrees, it freezes, in smaller ponds often overnight. In larger water bodies, wind and wave action mix the water on the surface, making freezing slower and less sudden. 

It is good that water is most dense at 4 degrees Celsius. If water were to be most dense at its freezing point, 0 degrees C., surface water would sink at 0 degrees, and lakes would freeze from the bottom up! We would then be swimming in water overlying a mass of ice, waiting for it to melt much later in the summer, if ever, and there would be no fish to catch, no osprey or fishermen to watch, but only a mist rising from the cold water into the summer air.