April 21, 2005 Central Missouri Chase

by John Farley

The first chase of the year for me was a good one - although it resulted in no tornadoes, I did see 4 tornado-warned storms, all of which were prolific hail producers and all of which produced wall clouds of various magnitude. The day was promising, with most of MO under a moderate risk as a triple-point low was tracking from northern Kansas into northwest Missouri, with a warm front to its SE from a little north of Kansas City to around Jefferson City and into southeast MO. Actually this was more a stationary front than a warm front, having been a back-door cold front the night before, but as the low approached it was progged to push back north as a warm front - how far being somewhat uncertain. My logic in choosing central Missouri as a target is explained in the post I made to the Stormtrack FCST thread at mid-morning on the day of the chase, April 21:

I am planning on targeting an area farther east in Missouri [than the path of the anticipated triple-point low, a little north of Kansas City], tentatively around Hermann or Union. This is partly a matter of how far I can drive in the time I have, as well as a desire to avoid the poor chase terrain in SW MO (though the Union area ain't so great in that regard either), but also based on the decent helicity (especially in the lower levels) along the warm front across central MO. This shows up on both the RUC and NAM models, though NAM has it a little farther north (which would be better in terms of chase terrain, but I suspect that, using more current data, the RUC may be more accurate on the frontal position). I do think that if a storm can ride along the warm front toward the SE or ESE, it may be able to get enough storm-relative helicity to make things interesting. Depending on where the storms develop, crossing the MO river could be an issue in keeping up with the storms, as bridges are limited across central and east-cental MO west of the STL area.

I headed out the door at 1:35, for a target in the general area of Columbia, Fulton, or Hermann, MO. I decided to head west on I-70, remaining initially north of the Missouri River, figuring that even if the storms initiated south of the river, the area of storms would gradually shift to the NE if, as predicted, the warm front pushed to the northeast from its position as desribed above, which in the eastern half of MO placed it mostly south of the river. If need be, I could cross to the south side of the river at either Hermann or Jefferson City. By this time, a blue box had been issued for most of eastern MO and western IL, based in part on the expected activation of storms along the front and in part on southeastward movement of an MCS in far northern MO. However, I kept my target area as it was, at the western edge of the watch box or just west of it, anticipating better dynamics closer to the low.

By around 3:00 or a little earlier, I had reached the Flying J one exit west of Warrenton on I-70, and used their WiFi for a data check. An intense, isolated storm had developed to the WSW of Columbia, with a smaller, weaker storm to its southeast. The larger, stronger storm had very much of a supercell look to it, and it seemed on the radar animation to be tracking east on a path that would take it just south of Columbia, perhaps hitting the south side of the city. I would proceed west to either route 54 at Kingdom City or route J at Lindbergh and proceed south to intercept. For the rest of the way, I was able to track the progress of this storm and others that occurred later on either NOAA Weather Radio (NWR) or a local Columbia radio station that had its met on live almost continuously through the afternoon. These sources soon told me the storm was SVR warned for Cooper Co. The radar reports indicated that its movement was sufficiently slow - 15 to 20 mph - that it made sense to get as far west as I could before turning south, so I proceeded on to route J and cut south there. By then, the western sky was quite dark, and a little anvil rain began to fall. As I got closer to the storm, SVR warnings were also issued for Moniteau Co, and were soon upgraded to a TOR warning for Moniteau Co. and later, southern Boone County.

By the time I reached Millersburg, it seemed apparent that the storm was turning to the right a bit, based both on the reported positions in the warnings I was hearing and my own visual observation of the storm, which from this angle seemed to be producing widespread rain between me and the reported location of the meso. I decided my best bet was to go as far south as I could on J, to get east of the meso's reported location approaching Ashland. Should I end up too close, there were varous eastward escape routes along the way. However, at this time I made an annoying navigation error, following route F rather than route J where the two split. By the time I figured this out, my best recovery plan was to continue on to route 54, then go SW toward the path of the storm. By the time I was due east of Ashland, it was obvious that the storm had continued its rightward path and was now moving toward the SE or ESE (though the radar reports still described it as moving east). I could now see a ragged, scuddy area under what was apparently the meso, through the rain at first, but then I got an occasional clearer view through gaps in the trees. I also noticed (and heard reports on the radio) that other storms to the SE of the one I was targeting had intensified rapidly, to the point that my storm and a couple to its SE were beginning to interact. I exited route 54 somewhere around Lake Mykee - I think at route AE between New Bloomfield and Lake Mykee - and turned right (north) on AE (I think) at the T intersection I immediatedly encoutered after exiting. There was a hill there that would allow me a better view, and when I got there I could see the ragged, scuddy meso off to my WSW. I was actually sitting next to a radar of some kind; perhaps a TV radar? About this time, a TOR warning was issued at 4:40 p.m. for southern Callaway Co., right where I was, based on radar indication of strong rotation 7 miles NW of Holts Summit. Obviously this was the meso I was watching, as my location was about 6 miles NNE of there (if I was where I think I was). Also, minutes before the TOR was issued, the storm produced golfball hail 3 miles south of Ashland along U.S. 63. In addition to the meso to my WSW, I noticed a very strong and low updraft base to my south from the next storm SE.

Gradually, the meso came closer, but did not show any indication of being about to produce a tornado. Still, I did not want to let it pass right over me (or just to my south, which would put me in the hail core), so I knew I needed to bail south. I turned around on the road I was on and did so; fortunately the road was just in the right place to let me thread my way toward the small bright spot between the updraft of the storm to my west and the rapidly intensifying updraft of the one to my SE. Somewhere around or just south of Lake Mykee, I think a little before 5:00 p.m., I stopped again and watched the meso, which was both shifting to the SE and changing in form to look less like a wide wall cloud and more like a shelf cloud as precip began to punch in behind it. It did, however, have a very impressive inflow tail at its north end. I did not catch the locations, but a SVS at 4:48 placed the radar-indicated tornado near New Bloomfield (where I had just been), with a new tornadic radar signature on the next storm SE, near Wainwright. The latter was described as moving NE and the former continuing to the E, so it was a matter of time until these two storms merged. Soon I moved south once again, stopping a mile or so south in a parking lot. At this time the meso was almost over me, and I noticed a small area of weak rotation in the clouds perhaps a mile to my W. I got a little more video, including this shot of the north end of the lowering almost overhead, then bailed to route 54 and ducked south to get out of the path of any possible wrapping hail. At 5:10, another chaser reported golfball hail at Lake Mykee, where I had been minutes earlier.

I decided my best bet was to drop S. to route 94, which follows the Missouri River. This was my only east option north of the river, and it could give me position either on my storm or the one to the SE, which by now, unbeknownst to me, was producing hail up to 2.5 inches around Wainwright, damaging a number of vehicles including that of a chaser whose rear window was broken out. By the time I got to 94, the storms had apparently merged, and although to my northeast I could see the wall cloud of the "middle storm" - the next storm southeast of the one I had been on, it was rapidly wrapping up in rain and hail, and did not appear chaseable with the limited road options I had. But across the river, to the SE, was another tornado-warned storm (though at first I was only aware of a SVR warning on it) which exhibited a broad wall cloud and inflow tail. I watched this for a few minutes, and it seemed to be getting farther away, suggesting movement to the E or SE. Since it was reported as moving E at only 15 mph, I figured my best bet was to cut back to route 54, cross the river, and head east on routes 50 and 63. I did this, but this forced me to go through Jefferson City, where I hit a construction area and several red lights before getting to the faster part of the road. I was afraid the storm might have gotten away from me, but it was in fact drifting very slowly to the SE, so I was able to catch up.

I was pleasantly surprised to find, upon reaching a good viewing point east of Jefferson City around 5:20 or 5:30, that I had a great view of an impressive wall cloud right in front of me, to my E or ENE. About 10-20 minutes earlier, radar had placed the circulation near Bonnets Mill, and the wall cloud I was watching would have been a little south of there. Here is a video capture of the wall cloud when I first arrived. To the south of the wall cloud, to my SE, was some rising scud and general violent cloud motion; it was harder to tell of the wall cloud was rotating but its rear side did appear to be moving to the right, or south. Here is another video capture about 5 minutes later; the wall cloud looks slightly less organized and has moved to the right (S or SE) from its earlier position. After a few more minutes I hear at 5:40 that the TOR warning for Osage Co. has been reissued, with the circulation indicated near Rich Fountain, about 10 miles to my SE. Time to move!

To get to Rich Fountain, I had to cut south on U.S. 63, then east on route E. It was, incidentally, obvious that I would get totally cored and probably encounter some serious hail if I continued east on route 50 - both this observation and the new radar report indicated that the storm continued to move SE. By the time I got headed east, it was obvious that the meso had wrapped up in rain and if there was a tornado with the Rich Fountain meso, I was not going to see it from this direction. In fact, both the first storm I was on and this one seemed to be cycling, with one meso wrapping up in rain, only for a new one to form to the south or southeast. This, I think, accounts for the southeastward movement of the storms, especially considering that the radar often indicated eastward movement based on the movement of the main areas of precipitation. Looking at the map, I saw that a couple miles east of Rich Fountain there was a south option, which might let me get a better angle on either the now rain-wrapped meso or any new one that developed under the updraft base to my SE. And it looked like that was a possiblity, as small lowerings like this one were visible to my SE at a stop near Rich Fountain. Although this looks a little like a funnel cloud, I could not see any rotation. I hoped the storm would get east just enough that I could make it to the south option without getting cored, but that was not to be. As I tried to nudge the backside of the wrapping precipitation, I encountered hail that quickly grew in both amount and size. Seeing the trend, I stopped and turned around in a dense barrage of mostly 1/4 to 1/2 inch hail, but a few dimes mixed in. This turns out to have been a good decision; this was a little after 6 p.m. and at this time, golfball hail was reported just 4 miles or so north of my location.

Unfortunately, road options can be very limited in MO due to the rugged terrain and limited crossings of rivers and streams. After route E, which I was on, there was no more east option for 10 or 15 miles. By then, the storm was hopelessly out of reach. I did, however, notice strong new towers going up to my south, which soon began to throw down a little CG lightning. Since they were in my path, I decided to kill a little time with a much needed pit stop in Vienna. After maybe a 10-minute stop there, I was amazed to see that the storm in front of me had intensified dramatically. Upon turning on the NWR, I learned that it was SVR warned. (A few minutes later it became TOR warned, but I did not hear that -for some reason only certain warnings were getting through on some NWR stations. Perhaps it is related to the fact that this area is on the cusp on 3 different NWS offices, Kansas City, St. Louis, and Springfield. Maries Co., where I now was located, is in the SGF CWA). Anyway, I found a nice hill south of town with a great view and watched the storm for about 20 minutes. It did develop a nice lowering and produced a couple hail reports, but after 20 minutes it seemed to be lining out and weakening, so it was time to work back to I-44 and call it a day.

After a quick supper stop in St. James, I was on the road on I-44 at 7:40 for the 2-hour drive back to Edwardsville. On the way I was treated to some nice anvil-crawlers on the back side of the storms that moved through the STL area (producing numerous hail reports). I was home about 9:40; total chase distance was about 380 miles. As always, I would love to hear by email from any other chasers who may have been on this storm.

John Farley
Edwardsville, IL

Local Storm Reports:

From the “northwest” (Moniteau/Boone/west Callaway Co.) storm:

0330 PM     HAIL             CALIFORNIA              38.63N 92.57W   
04/21/2005  0.88 INCH        MONITEAU           MO   LAW ENFORCEMENT  
0400 PM     HAIL             3 NW JAMESTOWN          38.80N 92.52W   
04/21/2005  1.25 INCH        MONITEAU           MO   STORM CHASER      
0410 PM     HAIL             JAMESTOWN               38.77N 92.48W   
04/21/2005  1.00 INCH        MONITEAU           MO   LAW ENFORCEMENT   
0430 PM     HAIL             3 S ASHLAND             38.73N 92.26W   
04/21/2005  0.88 INCH        BOONE              MO   EMERGENCY MNGR    
0435 PM     HAIL             3 S ASHLAND             38.73N 92.26W   
04/21/2005  1.75 INCH        BOONE              MO
0510 PM     HAIL             LAKE MYKEE              38.68N 92.10W   
04/21/2005  1.75 INCH        CALLAWAY           MO   STORM CHASER      

From the “middle” (far southern Callaway Co. and northern Osage Co.) storm:
0505 PM     HAIL             2 NW WAINWRIGHT         38.60N 92.09W   
04/21/2005  2.50 INCH        CALLAWAY           MO   STORM CHASER      
0505 PM     HAIL             2 NE WAINWRIGHT         38.60N 92.04W   
04/21/2005  2.00 INCH        CALLAWAY           MO   STORM CHASER      
            ON HIGHWAY 94  

0510 PM     HAIL             TEBBETTS                38.62N 91.96W   
04/21/2005  0.88 INCH        CALLAWAY           MO   STORM CHASER      
0512 PM     HAIL             TEBBETTS                38.62N 91.96W   
04/21/2005  1.75 INCH        CALLAWAY           MO   TRAINED SPOTTER   

From the “southeast” (Osage Co.) storm:

0510 PM     HAIL             LOOSE CREEK             38.51N 91.96W   
04/21/2005  0.88 INCH        OSAGE              MO   STORM CHASER      

0525 PM     HAIL             15 SW CHAMOIS           38.52N 91.97W   
04/21/2005  0.75 INCH        OSAGE              MO   TRAINED SPOTTER   
            AT HWY 100 AND HWY C.  
0535 PM     HAIL             15 SW CHAMOIS           38.52N 91.97W   
04/21/2005  0.75 INCH        OSAGE              MO   TRAINED SPOTTER   
            AT HWY 100 AND HWY C.     

0601 PM     HAIL             1 SE LINN               38.47N 91.83W   
04/21/2005  1.75 INCH        OSAGE              MO   TRAINED SPOTTER   
0605 PM     HAIL             LINN                    38.48N 91.84W   
04/21/2005  1.00 INCH        OSAGE              MO   LAW ENFORCEMENT   
From the Maries Co. storm:

0658 PM     HAIL             7 S (VIH)ROLLA/VICHY ARP38.03N 91.77W  
04/21/2005  1.25 INCH        MARIES             MO   LAW ENFORCEMENT