Before we get started there’s one critical thing you need to know: there are always exceptions to the rules. Even with a forecast low of 39ºF in Huntsville for Thursday morning, we know some of our usual cold spots will be significantly colder than that. Take these two Tweets for example this morning – the first is from Vic Bell on Lookout Mountain, the second from Steve Talley in Crossville (Sand Mountain):
So, is it safe to plant tomatoes, flowers, etc?
For about 95% of the Tennessee Valley, the answer is “absolutely, yes!” That other 5% covers very small “microclimates” that can see frost as late as the first or second week of May. Having done weather in Alabama for almost 10 years now, I’ve made a lot of friends who live in unique areas of this state.
Places like Black Creek (Vic Bell’s area), Muscadine in Cleburne County, Valley Head in DeKalb, Winchester in Franklin County, Tennessee are among these “microclimates” that don’t fit the mold of the “one number forecast.”
The low temperature map from this morning is a great example of how much variation there can be:
Huntsville’s latest freeze on record occurred on May 2, 1909 (probably the same year that snow fell and the sprouting corn crop froze – can’t find documentation on that, but I believe the stories).
Muscle Shoals’ latest recorded freeze happened on April 27, 1919.
There are two factors to consider here: historic data and future guidance.
History is on our side; May 2 is the latest freeze in over 100 recorded years of springtime cold snaps.
The guidance is on our side as well. The graph in the gallery below shows the NOMADS ensemble probability of a temperature dropping below 35ºF at Huntsville International Airport through the end of April.
That gives us high confidence that frosts and freezes will be a thing of the past for most of the Tennessee Valley, Central Alabama, and Middle Tennessee by Friday.
Just remember, if you are in one of those microclimates that is typically colder than other areas, there is still a slim possibility of frost until early May. I don’t expect you to get that cold again, but that small chance is something to be mindful of as you plant flowers and garden vegetables!