www.ksuturf.org/Weather/ 

Ever wondered what the actual soil temperatures are.  This tool gives you a realtime temperature at 1" and 4" depths.  What amazes me is how much it varies from day to night this time of year.  Seed germination takes twice as long when soil temps dip into the 50's and 60's at nightime like they are right now because it is only growing during the daytime (warmer) hours.