Beware the Inverted-V and Here's Why...

         With the warmer temperatures and severe weather season well underway, you may have heard me or other meteorologists mention the term "Inverted-V."  Unless you happen to be a weather geek like me or decided to google it after reading this, you've probably thought to yourself "is he talking about a mega wedgie"? 

        No I swear, the Inverted-V isn't another name for a wedgie...it is another way meteorologists describe an atmosphere that features relatively drier air near the surface. More specifically, the name originates from weather soundings that feature larger temperature-dewpoint (dewpoint depressions) spreads near the surface compared to the atmosphere, which resembles an inverted-v shape. 

An Inverted-V Weather Sounding (Depiction of Atmospheric Conditions) Courtesy Of wasatchweatherweenies. Red line is temperature and green line is dewpoint. As seen in the sounding, the red and green lines split and are far apart in the lowest portion of the atmosphere, representing air that is warmer but drier than the upper atmosphere. 

        As it relates to severe weather, as thunderstorms form at the higher levels, the initial precipitation falls through this drier layer of air and some of this precipitation evaporates.  As evaporation takes place, this begins to cool the air, creating a denser airmass that gets entrained into the downdraft of the thunderstorm. This leads to faster acceleration of this air to the ground due to negative buoyancy, providing for a stronger downdraft.     

        Ok, that's cool but so what? Why is this something to pay attention to or call out? The short answer: these profiles (assuming all other parameters are in place) generally lead to damaging wind events in our neck of the region due to the presence of drier, evaporatively cooled air, which is more dense that warm, moist air. As we approach the summertime, these Inverted V profiles and midlevel microburst profiles are something to watch for as these can bring damaging winds and heavy rain bursts. Moreover, the very hot summertime temps exacerbate the temperature-dewpoint depression further, leading to an increased risk at seeing damaging winds during summertime severe weather setups. Alas as I always say, beware the Inverted-V