April 26, 2009
Editor: Putnam E. Reiter
Risk Area: High Risk
Initial Target Area: Altus, Oklahoma
SPC Case Review
The main difference between yesterday and today was the expected approach of a shortwave trof into the region. Wind speeds were expected to improve with decent instability. A concern was model progged development of widespread showers and thunderstorms across the threat area during the morning hours. This did not occur as only isolated development happened. A bigger problem was the widespread clouds across the region, which kept CAPE values around 2500 J/Kg or lower. Another issue was moisture mixing out in Texas, which lowered CAPE values in this area.
Storms developed by noon and a tornado watch was quickly issued. These initial storms dissipated with little coverage. Other development continued along the warm front in far northwest Oklahoma. By mid-afternoon, clearing occured in the western Texas panhandle. CAPE values rapidly jumped into the 2500-3000 J/Kg range and a severe thunderstorms quickly formed. This storm moved into northwest Oklahoma and produced several tornadoes. It was a strange storm structure was elongated cores and cell mergers. Either way, lots of chasers got these tornadoes on video.
In southwest Oklahoma, a severe thunderstorm moved northeast from Texas into southwest Oklahoma. This storm continued moving northeast and produced tennis ball hail in Texas. It tried to produce a tornado near Snyder but lowered CAPE values from Texas likely prevented such. It eventually moved into Canadian County where it lost its structure and become part of an MCS.
Other storms developed along the dryline in northwest Texas and moved into far southwest Oklahoma. There were numerous storms on this line and they likely interfered with each other. These storms attempted to remain supercellular but eventually became part of the growing MCS.
The Chase –
Team 1 – David Underwood, Rob Ferguson, Brett LaBare and Putnam Reiter
Miles Driven – 300 – Gas spent $24.00
Departure Time – 14:30 CDT
Return Time – 21:15 CDT
We left Oklahoma City and headed southwest on I-44, reaching Lawton we went west on HWY 62 to Altus. We got to Altus and got some food and hung out at the Holliday Inn. We watched RADAR, seeing the storm to our south and the storms up northwest. Knowing that we could not get to the storms northwest, we decided to focus on the storm to our south. This storm was well established and was moving into Oklahoma. If we waited it out, we would be able to fall in right behind it. We also noted the storms to our southwest, but weren’t real impressed with them.
We took off and went south on HWY 283 out of Altus. As we drove south, we saw the back edge of the storm, which was quite impressive. The storm had a nice hail shaft and great flanking line. We got to HWY 5 and decided to watch the storm. We knew we couldn’t go east or south, so it was just best to sit. After waiting about 15 minutes for the storm to get by us, we started east on HWY 5. Getting to Tipton, we could see the storm was well north of HWY 5 and we kept going. When we got to Manitou, we turned north on HWY 183 and got into the inflow notch.
The storm looked to have organized and we were closely watching the lowering. We also knew there was no way we could make it to HWY 62 before the storm did, so this forced us to section line roads. Luckily these roads are gravel improved and we managed to navigate them just fine. As we got close to HWY 62 the storm’s organization significantly improved and it had a rapidly rotating wall cloud just off the deck. This led to some excitement on the amateur radio but all the reports were good.
The RFD blew out the updraft and the storm quickly lost the lowering. We traveled north on HWY 54, knowing that we had some really bad road choices due to the wildlife preserve to our east. So, we drove up to HWY 19 and waited for the storm to get north of us. Once it did, we headed east on HWY 19 and raced to get back in the inflow notch. We got on HWY 115 north and noticed some improved organization. Staying with the storm, we had to turn east on a section line road to get over to HWY 58. About halfway through this trip, we saw power flashes under the updraft area. We called this in and luckily the TV cameras also had the same thing. It appears that some wind hit two lines that kept arching. It was under a lowering and of concern.
We turned north on HWY 58 towards Carnegie and noticed the base was rising on the storm. We weren’t that impressed with it any longer but stayed with it. After some section line road problems we went east on HWY 9 and north on HWY 146. By this time the storm didn’t look good at all and we decided enough was enough. Eventually we saw an updated RADAR and the developing MCS.
Lessons Learned –
– The only thing here is my rant against SPC. Of all the freakin’ stupid risk areas to issue. This is the most bogus risk area I have ever witnessed. Oklahoma has not had a high risk since May 2004 and we broke the streak with today. I cannot believe a high risk was issued today. I thought the moderate was good, but even a stretch. I wasn’t interested in chasing today as I just didn’t think it was that great. Sure enough I was right. The storm in northwest Oklahoma was cool and it produced a tornado. However, that was it and significance wise nothing else, not even big hail. SPC did one thing worse, they continued the high risk at 8pm when an MCS was forming. The most exciting thing was the OKC TV guys proclaiming the end of the world. This is yet another reminder that the SPC outlooks are guidance, nothing more. As Andy said, “there is only one April 26th!”
Engaged Storm: Tipton
Tornado: No – ohh so close.
Hail (larger than 0.75 inches): No
Wall Cloud: Yes
Wind (above 57.4 mph): No