3 days of 50 degrees is what I was taught, not sure on night time lows or soil temp though.
http://www.dtnprogressivefarmer.com/dtnag/view/ag/printablePage.do?ID=BLOG_PRINTABLE_PAGE&bypassCache=true&pageLayout=v4&blogHandle=production&blogEntryId=8a82c0bc179eb30701185b5f01b308b6&articleTitle=Breaking+Dormancy+in+Winter+Wheat&editionName=DTNAgFreeSiteOnline
75 degrees in KS tomorrow
