After several weeks of temperatures well above freezing, tonight might be the last night until the fall where readings may drop to or just below freezing. The National Weather Service has issued a Frost Advisory which goes into effect late tonight and will be in effect until mid-morning on Sunday. It includes most of the counties in Iowa north of IA Hwy 92. Even to the south of IA Hwy 92, readings will also fall into the mid-upper 30s and some precautions might need to be taken there as well as in the Frost Advisory area. This will be the last frost (For sure!) until October.