I wound up intercepting four separate storms yesterday. Now comes the challenge of condensing a very busy chase into the written word…
Given the Enhanced Risk issued by the SPC for my chase region I paid very close attention to short term models, surface observations, and satellite images Monday morning, April 20th. I was especially intrigued by the SPC text in the risk statement that spoke of the potential for rotating storms. With instability, shear, and moisture in place the approaching cold front – and the associated lee trough – was the forcing mechanism I was expecting to fire storms.
After closely examining the models and surface obs and following a phonecon with the local TV station to plan some details I headed down the driveway at 1 pm. Motoring to Glade Hill along VA Rte 40 in Franklin county I parked to watch and wait, fully expecting towers to start punching upward by 2 pm. After a bit I spied a line of towers that was going up just to my south:
In order to maintain an intercept position on this line I moved east along Rte 40, finally turning south on the Climax Road to stop at a favored ridge top vantage point. From there I could see updrafts and even an anvil. However on radar these storms were still west of I-81 and weren’t moving toward me at all. (That was the first hint that the setup might have differed from what I had seen.) Still I expected these cells to move east off the mountains – per the short-term model solutions – and thus I’d be in a good position to intercept.
I should also mention that during much of this chase I was in contact with several other chasers, a very unusual situation here in the Old Dominion. Kevin Myatt was also out this day and had initially located in Chatham along U.S. Route 29 in Pittsylvania county. While I was stopped along the Climax Road he decided to dive south into North Carolina to check out a storm moving northeast. When I peeked at this cell on radar I immediately noticed that (a) it had a classic supercell signature, (b) it was splitting as I watched, and (c) the right hand split looked very “tornadoish.”
That was exactly what I had been looking for but further south than I had expected. I dithered all of 30 seconds before deciding to totally abandon my initial chase area and go after that cell. Maneuvering over to Rte 29 I rolled south at highway speeds as the two halves of the split became visually obvious. Just north of Blairs I diverted east on a side road to check out the northern split, which was now severe-warned. It showed some rotation on radar and had a wall cloud underneath it:
Although I was in a great position to stay on this cell I was pretty sure it would weaken quickly (a la many left hand splits). Moreover the right hand split was now tornado-warned so I pressed on southward. Unfortunately I was not in a good position to intercept this cell as it had turned right – typical of such splits – and the business end was still in North Carolina, due south of me as it steamed eastward.
Again using highway speeds I zoomed south to Danville and then east on U.S. Route 58 to get ahead of the storm. I wound up diving south about halfway to South Boston via Virginia Route 119, turning east at Semora NC. I stopped for a bit on a farm field entrance to video and take photos but then quickly abandoned that position as the rain closed in. Continuing southeast I reached a crossroads where I met up with some Hokie Stormchasers whom I’d also been in contact with.
Together we pulled off to watch the business end of this storm approach. It had obviously weakened from its earlier peak and was no longer tornado-warned. Still, it appeared to be trying to organize and looked like it had an RFD cut on it:
As the storm continued along we motored further east to Roxboro NC where I wound up pulling off the road to prepare for the 5 pm broadcast of the Roanoke TV station. I switched on the livestream and sat for ~20 minutes to do a phoner with the on-camera meteorologist. As I waited a flanking line built southwest of the main storm and the new cells became severe-warned. Fortunately the bulk of the line stayed just west of me and my livestream showed this base during the TV phoner:
After the phoner I pulled up stakes and continued north to follow the storms but their trajectory kept me from regaining a good chase position. I did get a good glimpse of mammatus just before reaching U.S. Route 58 again east of South Boston:
At this point I called the chase on this line and motored west through the South Boston area toward Danville in hopes of catching storms along the cold front as they moved eastward (or so I thought). However as I approached Turbeville a small cell just ahead of me tempted me so I diverted onto a side road and stopped to film and watch it:
This storm split before my very eyes and the right hand split moved north toward…South Boston! So I turned around and rolled back in that direction to see what this cell might do. By the time I reached the area two things were obvious: the storm was steaming northeast at a pretty good clip and I needed a bathroom break. Since the two factors were mutually exclusive I decided to let this one go and made my potty stop.
I grabbed a quick dinner in South Boston and motored north on U.S. Route 501, turning northwest at Volens on Cody Road. With lowering sun angles and convection now to my east I had to stop and snap a few photos:
As I continued westward toward home I noticed on radar that storms were still lined up along and west of I-81, several hours after I’d expected them to translate eastward. That was another hint that the day’s setup had gone awry. It appears that the cold front hung up over the mountains and thus it – and the associated lee trough – didn’t provide the forcing required to fire up storms near my initial chase location.
It was still a productive chase, but I do prefer NOT having to chase down storms from difficult angles. It is much more preferable to be in position and let them come to me!