USA National Phenology Network What is Phenology?
"Phenology, which is derived from the Greek word phaino meaning to show or appear, is the study of periodic plant and animal life cycle events that are influenced by environmental changes, especially seasonal variations in temperature and precipitation driven by weather and climate."
Quote from USA National Phenology Network Home Page:
http://www.uwm.edu/Dept/Geography/npn/index.html Other USA Phenology Networks
LINK:
http://www.uwm.edu/Dept/Geography/npn/npn_...tadatabase.html
Scroll down through the page to look up data for your home state. No guarantee that some of the data will still be available since some of the links are bad.
So this will be an exercise in Internet sleuthing....your mission will be to find some good links and data!
Here is something I found about three clicks away from the main USA Phenology Networks page:
National Snow and Ice Data Center 
http://nsidc.org/data/lake_river_ice/freezethaw.html
This data pertains to Global Lake and River Ice Phenology. This interface allows the retrieval of freeze dates, thaw dates, and freeze duration for some of the world's lakes and rivers.
Use the following link as a guide describing the features of the Global Lake and River Ice Phenology:
http://nsidc.org/data/lake_river_ice/ 
Linear Mode
