June was certainly a month to be reckoned with! The National Weather Service issued more than 134 severe weather warnings with many areas receiving more than 200% their average monthly rainfall! I am afraid to say this wet pattern will likely be sticking around for the rest of the summer, which is very concerning, since we will be in the heart of hurricane season. Tropical rains falling on an already saturated ground could give us some serious issues. July is usually one of the wettest months of the year, if not THE wettest. We average 5.27 inches of rain from summer storms.
After what we all experienced in June, many have asked if I thought our summer storms were getting stronger. The answer is absolutely, 100% yes! They are not only getting stronger but more frequent as well. This is due to a combination of factors, like the warmer than normal temperatures, increased humidity, and changes in atmospheric patterns over the past several years. For the past 10 years we have seen a significant increase in temperatures, especially during the summer months. Warmer air can hold a lot of water vapor, which fuels thunderstorms. The warmer the air, the more water it can hold, which is leading to heavier downpours, more intense lighting, and a greater risk of flash flooding. In June, we saw an entire month’s worth of rain falling in just a few hours across many north Georgia counties. The National Climate Assessment and NOAA have both documented a significant increase in heavy rainfall over the past 10 years.
With hotter surface temperatures and more moisture in the air, the atmosphere becomes extremely unstable, leading to stronger updrafts (fuel for storm development), more storm warnings with severe winds and hail. Another thing I have noticed, and maybe you have too, is our storm season is lengthening. Ten years ago we used to have a peak in spring and early summer, but now it is well into late summer and even early fall. Flooding events are now more common here and also in our neighboring states of Alabama, and the Carolinas. As we have also seen this season, these are not just your pop-up afternoon storms. The are Mesoscale Convective Systems, which are organized clusters of thunderstorms that can last for hours and cover large areas. It is primarily from these MCS where we are seeing a month’s worth of rainfall in hours.
There is a bit of a silver lining to all of this. Summer heat. With more clouds and rain, it is less likely we will see any major heat waves this month. It is July and it will be hot, with an average high of 88 degrees. The Climate Prediction Center is giving us a 50/50 change of above or below normal temperatures. I am thinking near normal to below normal. We shall see!
Image: courtesy NOAA
