A slow-moving cold front is bringing scattered showers to the Tennessee Valley Saturday morning; as the front moves through, showers become more widespread just ahead of it and quickly taper off behind it.
The rain moves out before noon Saturday leaving us cloudy, cool and dry through early afternoon; some sunshine breaks through before the day is over, and temperatures stay in the 60s. Colder air moving in gives us the lowest temps since mid-April and a chance of some light frost in the ‘cold spots’ by Monday morning.
Sunday will be the ‘coolest’ day of the next week: 30s in the morning and barely getting to 60ºF in the afternoon with a chilly north wind and a sunny sky. The strong Canadian ‘high’ driving the cold air into the region sits just northeast of Alabama Sunday night into Monday morning, and if the wind can go completely calm, some of our usual cold spots like Valley Head, New Market, Winchester, and Russellville *might* see a little scattered frost as temperatures drop below 35ºF.
So who has the best chance of frost? It’s those microclimates scattered around here where it can get a lot colder than the Huntsville International Airport number that you tend to see in most weather reporting.
What’s a microclimate?
The American Meteorological Society says it like this:
‘The fine climatic structure of the air space that extends from the very surface of the earth to a height where the effects of the immediate character of the underlying surface no longer can be distinguished from the general local climate (mesoclimate
Our usual ‘cold spots’ are microclimates; the landforms around them and the lack of large-scale urban development help get those spots colder at night: especially when the difference-maker might simply be the wind. (Calm usually means colder, any breeze at all helps promote mixing, and that keeps the temp up just a bit).
If you get some frost, snap a pic! Send it to use at firstname.lastname@example.org or upload it using Live Alert 19!
Looking into next week: Monday and Tuesday start out cool and dry, but a slow-moving, rain-making storm system develops by the middle of the week and brings a good chance of showery, cool, wet weather by Thursday and Friday.
It’s a little too early to know exactly how much rain we will get; some guidance gives us lot, and some gives us very little. The farther south that system goes, the drier it will be in North Alabama and Southern Tennessee, so instead of flip-flopping rain chances on you as you start to plan through the next week, we’ll keep at 50% and adjust from there as needed for Thursday and Friday.