Good Friday Morning! The MCS from yesterday left some more stable air in its wake this morning and that translates to lower dewpoints. These cold pools are fairly fragile though and with southerly flow, the dewpoints will creep back up through the day.
That being said, the entire area is in a medium risk for severe thunderstorms today (2 out of 5 risk). Thunderstorms will develop first in the mountains and then slide south east. With lower dewpoints this morning, the thunderstorm fuel is much lower than yesterday. That being said, 2000 j/kg can still produce some strong to severe storms. For reference, yesterday’s thunderstorm fuel was above 4000 j/kg and some places even hit 5000 j/kg. That’s an explosive atmosphere. Those high values look to set up Charlotte, and east today. So today, expect thunderstorm coverage to be scattered again before it organizes better off to our east.
The main risks today will be damaging winds, frequent lightning, and large hail again. If thunderstorms train over an area for any length of time localized flash flooding may occur. Next week a heat wave is likely to impact us again. It might be beneficial to find a way to save some of this water to water your gardens with over the next two weeks. It could get pretty dry around here.
A Science Lesson
Yesterday our area received numerous hail reports. Some asked if it was normal to get hail in the summer. The answer to that is yes. We get some of our most severe weather in The Carolina’s in June and July. Though Spring, and to some extent, Fall are our taught severe weather seasons. I’ve attached a reference graphic for a visual perspective. This is MCS season and our thunderstorms in western North Carolina are aided by that “permanent, topographic, stalled frontal boundary.” Yeah, that is is The Appalachian Mountain Chain. Those mountains aid in storm development this time of year across Western NC and when storms reach above 10,000 – 15,000ft, the temperatures are below freezing. All of that water starts to accrete into hailstones. As the winds in the storm grow stronger, those hail stones are lofted higher into the atmosphere and continue to accrete. As they get too heavy for the wind to sustain them, they fall back toward the surface, coming into contact with other supercooled water droplets or hail stones. When and if the thunderstorm then strengthens again and pushes the hail stone back up into the atmosphere. The hail stones come into contact with more supercooled water droplets and new hail stones. They freeze together forming a larger stone. This process continues until the hail stone is too big for the thunderstorm updraft to hold it aloft and it falls all the way to the surface, while melting some once it gets below that 10-15k ft. freezing threshold. That’s not a lot of time for a hail stone to completely melt before making it to the ground. The largest hail isn’t usually found here though. It’s not out of the question to see quarter or half dollar sized hail here, and occasionally we can see larger. The largest hailstone ever recorded though is 8 inches. That hailstone fell in 2010 in South Dakota. Bangladesh holds the world record though. In 1986 a whopping 2.25 lb hail stone fell there. From 2000-2019 hail was responsible for 8 to 14 BILLION dollars A YEAR! Hail will kill livestock, damage vehicle, destroy crops, and reek havoc on rooftops. Hail is one of the costliest severe weather events across The Nation.