Summary: David Douglas and I intercepted a severe tornado warned cell near Medina, Tx right before dark. We witnessed funnel clouds, wallcloud, RFD slot, with SPC logged hail of up to 1 3/4" with warnings of baseball. Because of failing light, but primarily because of hilly terrain and trees could not verify a tornado - though we suspected there very likely could be one there. Very intense 'spooky' storm in this isolated area. I took some pictures and video.
Discussion: The day seemed like a tough call for some time. I had been looking at the models and maps for a day or so and was aware of the northern area in northern Tx and the southern area. One of the big issues of the day was the main mid level wave still out west and possible cloud cover and subsidence during much of the day. The other issue IMO was the fact that the NAM and RUC had two separate views on the 850mb winds. NAM believing the Mexican low would strengthen and dominate backing the 850's and thus improving tornado chances in the southern area in particular. The RUC solution favored the more northern area and even DFW vicinity.
With no real finalized identified target we left from Austin about 3pm or so and decided to head west to Mason which is often the nexus of severe weather in Tx in Spring. Along the way stopped in Llano and grabbed wifi data for awhile. This delayed our Mason arrival and I actually forgot that was our destination, but basically the idea was to head to the dryline vicinity and then based on obs and SPC Mesoanalysis, Digital Atmosphere maps, as well as satellite and radar decide north or south and hopefully something would 'break' and the weather would show it's hand.
It held out until the last minute. We finally saw just the smallest smudge of a precip area on radar aligned with a new N/S vis sat boundary which had just appeared through a nearby opening in the stratus and cirrus layer. With obs showing strengthening sfc low and backing winds down south with strong composite parameters per mesoanalysis we decided to head for sw of Kerrville. Using David's new gps toy (what was it Tom Tom something?), it did a wonderful job of keeping track and visually displaying roads and verbal commands. Cool toy David.
Once at Kerrville it was apparent we would have to race to beat the core and possibly the tornadic portion of our developing storm. It went from almost no reflectivity to quickly a very nice looking storm with obvious supercell characteristics. It then split at least once. Eventually Threatnet began showing us some 'whirlies' with speeds up to 115mph. Then we got several whirlies (shear markers). Storm movement was north or northwest to begin but eventually it right turned toward our path. Additionally and typically as usual in order to keep it interesting my vehicle started having to act up. I just had the head gasket replaced awhile ago and now the exhaust manifold gasket has a leak. As we were headed through and in front of the core trying to beat the tornadic portion my vehicle also started misfiring. David mentioned aborting, but I knew the tune to this song and played every note.
We continued on by me switching manually to 3rd gear instead of overdrive every big hill we came too. Not sure what is up with the vehicle. Good news is it didn't fail us this time. We rounded down to Bandera south and then took a road to the nw toward Medina and the mesos indicated on Threatnet. Visibility was fairly poor, and it was becoming twilight along with inflow overcast skies above. We really couldn't even see the storm until we were within 3 to 5 miles of the updraft. It was very dark ahead, with areas looking a bit brownish dusty and black IMO and very foreboding. As we topped one hill and flew by I looked to the southern end of the inflow area and saw what appeared to be an almost vertical slanted wall of demarcation to the ground. A possible tornado but only a glimpse in between trees and I was hoping to get right up on the features of desire. David and I drove as far as we could. The storm gods frowned on us and took us lower and lower into some type of valley with big trees and 2x4's next to them. (I had brief vision of a tornado coming through this area slinging these 2x4's at us.) This happens just as we were very near the tornadic features. It is never a good feeling to lose sight of possible tornadoes when you think one may be lurking about and gives you an uneasy feeling. We rounded a turn or two and eventually viewing got a little better. We could see the whole inflow area with lowered base and all, but there was still some smaller trees in the distance blocking view to the ground, and it continued to get darker.
We went as far as we could go. Any further and it looked like we would drive into the Abyss, and well I've been there a few times and I'd rather save that for another day. We stopped got out and viewed. I attempted to take some pictures in the now near dark, but I am out of practice at low light adjustments and shooting. The area was very alive with very strong inflow, a very dark wide area just in front of us, to the left (south) of that was a lowered wallcloud with somewhat a v shape at times. South of that we viewed some funnels. Eventually it appeared an RFD came in and wrapped around the wallcloud and obscured it with rain curtains. I pulled out the Vx2000 and it lit everything up and I could still see some of the features inside the rain but it continued to get darker. Later I saw what appeared to be a possible slanted tube tornado with a bend in it, but I can't confirm. We watched as long as it made sense then started heading home.
We followed the storm north of Bandera, all the way to Kerrville, and it began to fall apart. We drove through it through Fredricksburg and continued home through mist, fog, and light rain - none of which was showing on Threatnet for some reason.
It was a good chase, and my first of the season. The gps, Threatnet, everything but the vehicle was working well. I guess it is back to the shop.
We thought our storm was one of the best of the day, but it was hard to verify any tornado. Would have been nice to be on it sooner, but it was a tough call. I believe it was the first storm to show any shear markers on Threatnet, and one of the first to be tornado warned although I believe the Abilene storm was first at 3pm.
