As was predicted this morning, and has been for the past few days, severe weather struck the region this afternoon and evening. It was a difficult forecast, but it panned out as I expected. It wasn’t world ending, but it did give us some issues, and caused some damage across the region.
The atmosphere was primed thermodynamically (the part of the atmosphere dealing with temperature and moisture) speaking, at least. Clouds actually hung around pretty tough this morning, hindering the rising of temperatures for a few hours. However, after they cleared, temps quickly rose into the upper 80s and the lower 90s across the region, and in combination with 70 degree dewpoints, the atmosphere destabilized very quickly.
By the early afternoon, we had plenty of moisture, instability and an outflow boundary in eastern Missouri to work with. All of this combined to quickly produce a line of gradually increasing storms, that organized into a wind damage threat as it moved to the east and southeast.
It continued to intensify, and actually developed a cold pool. A cold pool is essentially just rain cooled air behind the gust front, and this is a key portion of any squall line that produces widespread wind damage. This helps to organize, accelerate and strengthen the squall line/MCS as it propagates along its path.
This cold pool strengthened as it moved into Tennessee, where temperatures were higher and had longer to increase after the morning cloud cover. This greater temperature contrast between the two air masses allowed the gust front to be a bit stronger over a larger area in Tennessee, and produce more widespread wind damage. Check out some of the tweets from across the region!
— Waled Tayib (@waledtayib) June 16, 2016
— THOSE DRONES (@briansiskind) June 16, 2016
— NWS Nashville (@NWSNashville) June 15, 2016
Power lines are down over Audubon Drive, per scanner.
— Caleb Chevalier (@CalebWNKY) June 15, 2016
— NashSevereWx (@NashSevereWx) June 15, 2016
Check out this roll cloud I just snagged in southern Warren County. Very neat! pic.twitter.com/SEenyzx2gU
— Landon Hampton (@WxOrNotBG) June 15, 2016
With the Morgantown Flooding yesterday, and this today, this week is the exact opposite of what last week was like. And we aren’t necessarily out of the woods tomorrow. A cold front will be dragging into a region with very warm temps (mid to upper 90s!), and still a fairly moist atmosphere as well. This should yield high instability values across the region, leading to the potential for isolated severe storms again for tomorrow. Be sure to follow the latest from @WxOrNotBG on Twitter and to keep up with the forecast post tomorrow morning!