7/19/2010 DISC: MO/IA/IL

[John Farley]

Interesting event last night in north-central Missouri - a couple supercells formed at the west end of the MCS that formed in southern IA and moved across northern MO and western IL. Total of eight tornado reports between about 9:30 and 11:30 from these supercells - probably some are multiple reports of the same tornado, but with the reports continuing for a couple hours these supercells, particularly the tail-end one, appear to have been pretty persistent in tornado production. I see a couple of the reports came from a chaser, so maybe we'll see a report here. Too bad it happened after dark, as the storms looked otherwise pretty chaseable. It appears that these supercells may have taken advantage of increased shear near where the synoptic front that produced the MCS intersected with an outflow boundary from the earlier MCS.

When the MCS moved through the St. Louis area around 2:30 a.m. it was no longer severe, but the frequency of the lightning, several flashes per second, was probably the highest I have seen this season.

Speaking of lightning, with the earlier daytime MCS there were two people injured by lightning in St. Louis, one a man who was working on plumbing in the basement of a building that was hit and was shocked through the pipes he was in contact with, and the other a woman who was sitting in the back end of a truck with her feet on the ground when lightning struck nearby and apparently traveled through the asphalt to her feet. Both will survive, but both serve as reminders that you don't have to be directly hit by the bolt to be injured.

 

[Dan Melby]

I was on that cell from birth in SC Iowa. It really intensified between Lineville and Mercer right before dark. Just as I was questioning why it didnt have a warning, the first one was issued. As for chasability, it wasnt the easiest of storms. The road options going east off of HWY 65 in that area are limited. Due to the sorms movement I had to go down to Princeton and come back north and east a bit to get a visual after dark. It is very hilly in that area so it added to the difficulty, but still a fun July chase!

 

[AaronPippin]

My target had been Princeton, MO all day. I drove to Princeton, then down to Chillicothe, then back to Princeton all before 7:00pm. Finally while sitting at the Casey's in Princeton, I start seeing the towers going up to the north. I cross over into IA, then go east to the first cell that fired up. I get on it near Seymore, and watch for 5 minutes before I can tell its starts rotating, and goes Tor warned. I watch the lowering of the wall cloud, and watch it become wrapped in rain. I had to go back to the west a couple miles to get back to a good road to go south on. And from then on I loose visual on anything note worthy on this storm. Next the storm near Lineville got the warning issued, and on radar had much stronger rotation noted. I made it down to hwy 136 and headed west. Like mentioned above by now it was dark. I turned down a smaller black top about 5 miles east of Princeton, and then turned back east on a gravel. Unfortunately for me this put me in the path of this storm. (See the tornado report for 5 miles east of Princeton) I got blasted by RFD as the circulation went very near my location. I went back to the north then to get to hwy 136. At this point a new warning is issued for northwestern adair county. (most everyone knows the Kirksville tornado last year) Kirksville is the county seat of Adair county. To make matters worse the area fair is going on this week. So at this point my chase has now become somewhat dampered by the thoughts of those at the fair outside unprotected. I called many of my friends that I knew were there letting them know the situation. Luckily fair staff began evauations quick enough to try to make sure everyone got out of there. --Anyway back to the chase. I followed 136 to 63 and cored that storm luckily it had been dropped from the warning and picked up my gf in my hometown and continued on south on hwy 63. Made it to hwy 36 and took that west to Bucklin. Took 129 west and went about 5 miles up it to see the lingering wall cloud and caught the tail end of the warning on the storm in eastern Linn and western Macon counties that I had previously been in and had all the reports with it. At this point I thought the chase was over and we headed south back to Bucklin, just as a new warning was issed in the exact same place again. Back north we head on 129. I go about 7 miles north this time. Saw and reported a very tight wall cloud to my northwest. I ended up following this storm back along 36 to near Macon before it finally dissapaited. Yet another tor warning was issed for central Adair county. Watch in almost horror as very strong rotation was noted on radar directly over the Kirksville area. I made it to the storm just as it was entering Macon county at La Plata (my hometown) and saw and reported another rotating wall cloud. The dropped the warning however and since I was back home I decided to call it a night at 2:00am. That same storm went on to rotate again and become warned again in Shelby county but I was done chasing and just watched it rain. Lots of flooding in the area here. Here at my house I measured 4.32 inches in the 5 hours of storms that came through here overnight.

Like Dan mentioned this area is relatively hilly so chasing was a problem. I wouldn't have normally chased at night, but this was my home counties and felt I was needed more as a spotter for my area than just a chaser.

Here are a couple of pics of the 2nd storm with a wall cloud in western Macon county as it was over the Ethel area

-Aaron Pippin