Total Distance: 1050 miles
Target Area: Manhatten, KS, to Hastings, NE
Chase Area: Belvidere to Auburn, NE
Maximum SPC Risk category: High

A nice outflow boundary was situated in a west-southwest to east-northeast boundary just south of the NE/KS border in the morning hours. A deep low was forecast to develop in northwestern KS as a strong trough worked out of the southwestern US and into the central plains. The situation looked like a pretty typical plains tornado outbreak, with very nice shear in the warm sector in KS and OK east of the dryline, which was located in western KS southward from the low. However, despite strong southerly flow for more than a week in the warm sector, only moderate moisture was in place (Tds generally in the 60s), which only yielded moderate instability and resulted in a pretty strong cap. While there was a small area between the edge of the instability (i.e. the dryline) and the western edge of the strong cap), we felt there was a pretty good chance of the cap holding along the dryline. So, we targeted the outflow boundary.

Total Distance: 400 miles
Target Area: Enid, OK, to Wichita, KS
Chase Area: Thomas to Arcadia, OK
Maximum SPC Risk category: High

Today looked like of the best outbreaks of the year as a very strong upper trough/low was forecast to move out of the western US, inducing a very deep low in western Kansas. Strong instability of >4000 j/kg CAPE was forecast across central KS, decreasing to ~3500 in northern OK and ~2500 south of I-40. With the deepening system, a very strong low-level jet (40-50kts at 850mb) was progged to develop east of the dryline. Our original target of north-central OK and south-central KS looked good, as that area had excellent low-level shear (250-450 0-3km helicity) and strong instability. Mid-level was progged to be best over central OK, with a jet max of 50-60kts over central Oklahoma by 0z. We'll later see again why you should stick to your target area.

Total Distance: 350 miles
Target Area: Shawnee to Henryetta, OK
Chase Area: Wetumka to east of Checotah, OK
Maximum SPC Risk category: Slight

Given the time of year, I just had to chase as I knew it would most likely be the last chase opportunity until spring. Moderate instability had built across eastern Oklahoma as a strong upper-wave opened and ejected into the northern plains by evening. A strong low-pressure system was to move across central Minnesota by late evening, dragging a cold front and dryline across central and eastern Oklahoma. I had been targeting northcentral and northeastern Oklahoma, but winds had veered to southwest across that area by early afternoon. Therefore, we opted to head east on I40 about 2:15pm.

Total Distance: 1040 miles
Target Area: Hill City, KS, to Kearney, NE
Chase Area: Hill City, KS, to Red Cloud, NE
Maximum SPC Risk category: Moderate

A relatively abnormal situation was shaping up for the central plains as a strong, negatively-tilted shortwave trough ejected out of a western US longwave trough. Nice shear profiles as well as moderate instability was forecast to developed east of a surface low in northeast Colorado, progged to move east-northeastward. Additionally, favorable supercell conditions were located south from the low, east of the dryline. While central Nebraska looked to have the best backed low-level flow, surface moisture was lower there than points southward. So, we targeted the central KS/NE border area, and left OUN by 9:30am.

Total Distance: 500 miles
Target Area: Wellington, KS
Chase Area: West of Wellington to Atlanta, KS
Maximum SPC Risk category: Moderate

We had spent a couple of days prior looking forward to June 12th. Decent vertical shear and strong instability were progged over much of eastern Kansas and Oklahoma. Original intentions were to head to northeastern Kansas, but it looked more and more like southern Kansas would be just as valid as northern Kansas. With that said, we headed out on I35 towards southern Kansas.

Total Distance: 460 miles
Target Area: Wellington to Wichita, KS
Chase Area: BUST
Maximum SPC Risk category: Slight

We left Norman / Moore knowing that there was probably a better chance than not that any convection would be inhibited by a decent cap. That being said, a nice juxtaposition of strong instability (3000-4000 J/KG CAPE) and good shear north of a resident outflow boundary across southeastern KS gave a too-good-to-miss scenario to us. We met up with several other chasers in Wellington and proceeded to meander northward to stay with the boundary and areas of best convergence. A few towers really tried to break the cap near Wichita by late afternoon, but none could hold for more than 10-20 minutes. Realizing that this was going to be a cap bust, we decided to check out the tornado damage south of Harper from the tornadoes on May 12th. After looking at the incredible damage, we headed home, storm-less. Seeing that damage and thinking of the incredible power of the tornadoes from May 12th made the trip worth it.

Total Distance: 475 miles
Target Area: Alva, OK, to Medicine Lodge, KS
Chase Area: Medicine Lodge to Anthony, KS
Maximum SPC Risk category: Slight

The chase of my career so far...

This day looked looked to be the best we've had for some time. However, as the day neared, the models continue to indicate a slowing of the upper wave in the west. This meant that the best mid and upper level flow would remain north and west of Oklahoma. Shear profiles, therefore, looked pretty meager for much tornadic action.

Total Distance: 500 miles
Target Area: Wichita Falls, TX
Chase Area: Ryan, OK, to Weatherford, TX
Maximum SPC Risk category: Moderate

We left OUN abt 1:00pm, headed south on I35, then west towards the tor-warned cell near Ryan... Saw some decent structure with this storm, but it was pretty outflow dominant, though it had a very nice shelf cloud for quite some time. Disappointed with the tornado prospects for this storm, we dropped south into Texas and headed into Nocona. It was at this time that we heard of the tornado warning for Love county (the storm we had just left), but discarded it as it looked unimpressive. Seeing on radar more storms to the south, we headed south out of Nocona, going through Montague and Decatur. We had some hope for a cell that was in Jack county, but talk on local spotter network, as well as confirmation by radar while we were in Decatur, showed us that this storm was poor. Feeling rather disappointed, we decided to take one last shot by aiming towards a cell to our southwest in Palo Pinto county.

Total Distance: 175 miles
Target Area: Duncan, OK
Chase Area: Duncan, OK
Maximum SPC Risk category: Moderate

Well, I didn't like today from the beginning. With shear vectors along the front in OK, the storms were likely to go linear rather quickly. Additionally, ~700mb is quite weak. Again, like Weds., mid-level flow was quite weak, which tends to favor HP formation. As it seems, the cell south of Lawton was HP before gusting out...

Total Distance: 400 miles
Target Area: Pauls Valley, OK
Chase Area: Norman to east of Ardmore, OK
Maximum SPC Risk category: Moderate

Well, I had a dynamics exam at 3:30-4:30, so I was worried about getting a late start. By the time we packed up and hit the road, the OKC supercell was already in the city... We started driving north to that cell, but saw a nice storm just to our south (southwest of Norman). So, we turned around and headed for that storm. Stopped near Purcell to watch a couple of nice, very low wall clouds. As it crossed I35, we decided to ditch it because it appeared to be outlfowing out, and the fact that there were cells southeast of this one lead us to conclude the the southern one would disrupt and cut off inflow. So, we headed south then east then south. Drove through a couple of hail cores with mainly small hail (1"). Got some nice pseudo-wallclouds east of Dougherty in Murray county.

Total Distance: 450 miles
Target Area: Henryetta, OK
Chase Area: Okmulgee to Bixby to Muskogee, OK
Maximum SPC Risk category: Moderate

I actually liked the setup today more than yesterday. I liked the shear and instability. However, two things really got me excited: upper 60-s along the I40 corridor and points south, and a big fat boundary from south of Tulsa and southeastward. We all know what can happen when supercells interact with boundaries, so I was quite optimistic about the area bounded by OKC-Tulsa-McAlister.

Total Distance: 350 miles
Target Area: Elk City, OK
Chase Area: Clinton to Watonga, OK
Maximum SPC Risk category: Moderate

Left Norman about 10:30am, with a plan to head west on I40 to Clinton or Elk City. We picked these areas because they have good north/south options. At any rate, as we neared Clinton, we heard and confirmed two storms going up in far western OK -- one to the southwest of Woodward and one to the southwest of Sayre. We stopped in Clinton and spent about 10-20 minutes trying to decide which cell to go for. Despite hearing of the unconfirmed reports of a tornado with the northern cell, we figured we'd head to the cell near Sayre as it was closer, and we saw no reason why any either of the two cells would have a better chance at tornado-ing than the other.

Total Distance: 300 miles
Target Area: Duncan, OK
Chase Area: Waurika to Ardmore, OK
Maximum SPC Risk category: High

Models were having a difficult time with this system for several days leading up to this event. From earlier in the week, it was looking as if Wednesday would be the good severe weather day for the southern plains. However, the models slowed down the arrival of the main upper low with each run. By Wednesday night (the 3rd), it was quite obvious that a very strong upper low would kick out of the southwest US and induce rapid cyclogenesis in western TX by early on the 4th. The wind field was forecast to be very strong, with 500mb winds over 100kts across TX and into OK. The low was actually kicking out of northern Mexico, which left the mid-upper flow across the southern plains quite backed. However, a very warm and moist airmass (dewpoints in the mid to upper 60s) was advancing across northern TX and into OK ahead of the forming surface low. Shear was not going to be a problem; rather, limited instability was expected to be the main hindrance in what would otherwise be a significant severe weather outbreak...

Total Distance: 70 miles
Target Area: None
Chase Area: Union City to Oklahoma City, OK
Maximum SPC Risk category: Slight

I wasn't really planning on chasing today, since the environment only looked so-so for early-morning models, and I was wanting to save up for the coming weekend chase(s). However, the each RUC model run looked better and better for the potential of tornadic supercells in Oklahoma. A nice cell popped up near Elk City by mid-late afternoon and was moving into an environment characterized by 3000-4000 j/kg CAPE and 50-60kt 0-6km deep layer shear. Since it was close, I decided to hope on over to Union City to see what I could see...