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Given the convective setup I was decently excited about chasing Thursday June 23rd. The SPC had issued an Enhanced Risk for western parts of Virginia and the model parameters were looking good as a stationary front draped across the state.VA_swody1

The fly in the ointment was the morning passage of an MCS (some hinted at a derecho) across the area. In the past that has been the kiss of death for chasing as the lower atmosphere gets overturned and afternoon convection is typically squelched.

That turned out to not be the case this day. I took a quick jaunt out to a local vantage point to watch the leading edge of the MCS approach with an abundance of lightning and rain.CG from MCS

After retreating to the house to avoid most of the rain and re-engage with the short term models I ventured back out to a hilltop vantage point in Botetourt county to observe an eastward moving convective line (and stop by a local coffee shop for a snack). None of the activity was worth photographing so I headed home once again to decide on the chasing potential plus a target.

A close examination of the models, surface observations, and satellite revealed that the atmosphere south of the U.S. Route 460 corridor remained unsullied by the earlier convection. The sun was out in force and the convective parameters were very enticing. With abundant low level and bulk shear and CAPE (instability) the SPC’s estimate of the supercell composite parameter was >6 (anything over one is good for VA) and the significant tornado parameter for the same area was >1 (again, anything over one is good). So my forecast was that IF a discrete cell went up in this juicy area it would have no problems rotating. (Boy was I right!)

Thus my initial target was set as the Martinsville-Danville area along U.S. Route 58. But before I left for there I went to another local vantage point to peek at the still present convective line north and west of the Roanoke valley. Seeing nothing of note and feeling a cold outflow from the north I motored south and stopped at a rural spot east of Martinsville to watch and wait.

I didn’t wait long as an updraft to my north caught my eye. Even though the visibility was fuzzy (high humidity) the cell looked to be sustaining a lowering under it:Northern cell fm AxtonI watched for a few minutes before jumping back into the chasemobile, heading north to VA Route 57 and then northeast toward Chatham. This cell turned out to be a storm firing along the southern flank of the convective line and wound up too far north and east of me to catch.

I pushed east of Chatham to a crossroads to recheck radar and satellite. While there I noticed a fresh updraft to my west and my first thought was “Voila”! Rolling south and west via a rural road toward Tightsqueeze I stopped near an open field for this view:first photo of targeted storm nr ChathamVery soon thereafter I noticed a lowering under the base that was partially obscured by the treeline (hey, this IS Virginia chasing after all!):first view of lowering nr ChathamI quickly moved to a church parking lot just west of the trees and saw the wallcloud clearly:Yep that's a wallcloudThis cell wasn’t very impressive on radar at the time but I could hear artillery-quality thunder coming from the storm:IMG_4892Storm motion was southeast so the wall cloud was moving almost directly at me. When it approached close enough I vaulted a mile or so east to watch and film some more:Bigger wallcloud fm further EThe feature was very obviously rotating and grew larger in size as it neared. I had switched on the live feed while at the church so it was pushing out video while I recorded it locally. To keep up with the storm I frantically divided my attention between keeping one eye on the action and perusing maps for potential rural routes.

When the wall cloud got close enough I pulled back out on the highway and detoured east to a south-leading rural road I’d located on the map. This was an unpaved gravel surface on which I could only safely drive at 35-40 mph, which – of course – severely cut down my lead time for staying ahead of the storm. This photo was from a quick stop on a gravel turnout:Even bigger fm further S

Continuing south I found a path that led to the top of a knoll next to a field where I watched the wall cloud grow to a Plains quality magnitude:Oh myI stayed at this fantastic vantage point a bit too long. I realized it was past time to depart when I was craning my neck to look UP at the wall cloud as it neared. Oh, and this was the radar velocity view about this time:IMG_4910

I eventually made my way to U.S. Route 29 and turned south, stopping now and then to snap photos and enjoy the view even though it was moving away from the highway. To stay near the storm I dove east to VA Route 360, speeding happily along until I came upon a recent traffic incident that completely blocked the two lane road with a number of passersby already stopping to help. After a couple of minutes it was evident that no traffic was proceeding in either direction (and likely wouldn’t for quite a while) so I did a U-turn to find another route to get back to the storm, confident that enough helpers were already on the scene.

Finding an alternate route was easier said than done and I wound up motoring down a number of rural lanes while the now rain wrapped core of the cell kept just ahead of me. Finally working my way south to U.S. Route 58 east of Danville I used the highway speeds to catch back up, turning south on VA 119 as the core had already crossed Rte 58. Using more rural roads that criss-crossed the Virginia / North Carolina state lines I almost gave up on the storm…until I noticed this radar velocity view:IMG_4912

About this time I wondered out loud whether the National Weather Service would pull the trigger on a tornado warning (the storm was severe warned already). Thirty seconds later every alert I had with me went off confirming my wondering and all thoughts of abandoning the chase were gone. How could I drive away from a tornado-warned storm?

Continuing along rural roads and straining to keep the storm in sight I found this spot in Halifax county VA from where I found myself peering northward under the mesocyclone itself:tornadic mesocyclone in Halifax coThe rotation was visibly obvious but I didn’t dare get out of the vehicle as lightning was strobing down with alarming regularity. If there was a funnel or tornado at this point it must have been wrapped in rain as I didn’t see anything (neither did my dash videocamera). Apparently the local TV channel I chase for did a severe weather cut-in on this storm and used either my live feed or a picture that I’d send out via social media.

After this stop I pursued the storm further and wound up getting way too close to the mesocyclone for my comfort given the trees and unfamiliar topography of the area.This was the radar velocity view at the time I came across some small twigs and leaves strewn across the road:IMG_4914Amid atomized rain – a sign of very strong winds – I did a U-turn and beat a hasty retreat back the way I’d come.

I finally found a calm spot from which to watch the back edge of the storm, with one mesocyclone to my east and another one to the south:last look at mesocycloneThe video clip from this position shows awesome cloud motion and rotation that was thankfully moving away from me.

This was my last chasing stop of the day but now it was my turn to get chased. The convective line that had remained north for much of the day had sagged south and I had to beat feet south to Roxboro NC to avoid a large hail core coming right at me. I sheltered under a gas station awning with thoughts of filling the chasemobile’s gas tank but the lightning was too close and too constant.

Then radar indicated yet another mesocyclone and hail core coming toward me from the west so I left the gas station to pick my way northward up U.S. Route 501. I managed to avoid the worst of the storms but wound up detouring a good 40 miles out of my way home to do so. The last hour of the trip I plowed through heavy rain and lightning, all the more potent given that it was now dark. Home was a welcome sight!!

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