We come bearing good news! After struggling to see much of any rain for the month of June and into the first part of July, we’ve turned the corner over the past few weeks in the rainfall department. Over the last 30 days, many locations across the Tennessee Valley have seen a cumulative 4 to 5 inches of rain, with several locations in the 6 to 8 inch range. This hasn’t removed drought conditions for the whole area, but it has significantly worked upon improving those conditions. Still, there is a significant long-term rainfall deficit across southern Tennessee; so, we have to be careful with how long we stay in dry weather… but even those longer term deficit numbers aren’t quite as large as they were just a month ago!
So, now that we are into early August, we look ahead to what the weather may bring to our corner of the Tennessee Valley. To do that, we look at climatology for the area to get an idea of how the weather “typically” stacks up for our area for the month. Our local region’s NWS climate reporting station is at the Northwest Alabama Regional Airport in Muscle Shoals, and despite it being there, those numbers are also very representative of what is normal for the part of southern Tennessee that we service, in addition to northwest Alabama. Looking at the numbers, as you’d expect, August is a hot month here. Our average daytime high is 91 degrees, with that average high starting at 92 at the beginning of the month before easing down slightly to 90 as we round out August and get ready to head into September and the start of meteorological fall. We can certainly get hotter than that though! The monthly record high at the Muscle Shoals reporting site is 108, set back in 1930, and we can frequently have bouts of triple digit heat this time of year. Our average morning low is right around 70 degrees, but oddly enough, we have been as chilly as the upper 40s in the month of August during the overnight! The monthly record low for this reporting site is 47, set in 1917! Despite getting scattered pop-up thundershowers during many afternoons, outside of having tropical systems or the occasional thunderstorm complex, August is the beginning of the drier season for us that stretches through October. The average monthly rainfall for our area is around 3.77 inches. That’s certainly not good news considering the drought conditions we are currently dealing with!
The tropics are a significant concern during the month of August. While the full-on peak of the Atlantic hurricane season happens September 10th, there is climatologically a big ramp up in activity during the month of August, along with increasing frequency of major hurricanes. We start opening the door for the long-track Cape Verde type systems during this time as well. August has brought some memorable hurricane strikes to the Gulf Coast over the years. One only has to think back to storms like Katrina, Andrew, and Camille… just to name a few. As we know all to well, those tropical storms and hurricanes landfalling on the northern Gulf Coast can often bring post-landfall weather impacts far inland into the Tennessee Valley as well.
One of those inland impacts we have to think about is tornado activity. It is very normal for landfalling tropical systems to produce tornadoes in the outer rand bands on the right side of their circulation, relative to forward motion. Our area doesn’t see many tornadoes in the month of August from a historical standpoint, but when we do, they are almost always related to landfalling tropical systems. One such event was in association with Hurricane Danny in 1985. The remnants of Danny brought a significant tornado outbreak to the Tennessee Valley in August of 1985. Multiple long-track strong tornadoes (something that isn’t unheard of from tropical systems but isn’t statistically frequent) were spawned across north Alabama into southern Tennessee, including three separate F3 tornadoes within our viewing area counties alone!
