Yesterday's meteorological set up was perfect for monster storms to develop in Central South Dakota. Instead of monster storms plural, it was a monster storm that developed and realized the 6000+ CAPE that was present along and just south of the warm front. The tornadoes that formed from the parent supercell were spectacular to say the least. They reminded me of the Manchester/Woonsocket, SD tornadoes in June 2003.
The main question earlier in the day was if the cap was going to break or not...it did of course and convective initiation focused itself along the N-S Branch of the Missouri River near Lake Oahe which is located North of Pierre. The storm developed explosively...like a volcanic eruption says Rob MacDonald a friend/chaser from Ninette, Manitoba.
I was nowcasting for him yesterday to make sure he'd get up close and personal with this beast. He started in Pierre, SD and I got him to position himself somewhere along I-90 near Kadoka...I was trying to get him in position to be near the triple point. As heating and moisture got pumped into the region the warm front established itself North of Pierre, SD...I sent him there and he said that towers were trying to go up North of him but were hitting the cap. He kept rolling North and he was not far away when a tower finally broke through the cap and rooted itself in the boundary layer. He was closing in fast when the storm developed its first wall cloud and he was there when it put down the monster tornado. He has video of it, but the storm from certain angles had terrible contrast so he has video of the other touchdowns from the same storm. I'm so envious of him...this is a dream set up that yielded great results...
One lonely monster in great chase country, close to home (Canada), not late in the year, and great visibility early in the storm's life span before rain started wrapping into the tornado. Below is a low angle doppler velocity scan during the storm's lifespan...it had amazing gate-to-gate shear indicative of a tight circulation near the ground.
All-in-all it was a great day and I wish I was there...few more days Dave...I just hope the pattern remains active in the long range!
Below are videos that are surfacing from yesterday's tornado...they are INCREDIBLE!!!
I will add that storm chasing in the States is starting to turn into a $h:t show...too many chasers that don't know what they are doing. I blame Discovery Channel for this, they should be saying that only educated professionals should engage in storm chasing, one video below shows chasers running out of road yesterday as a dying tornado closes in. They ended up driving through a freshly planted soybean field. Terrible!!! This is making us look bad, someone is going to get killed and that will ruin it for the rest of us who take storm chasing seriously!
So CoD missed the worst of it because of bad roads and then because of downed power lines.
ReplyDeleteBut, they stayed safe and more or less kept sane.
I couldn't let the second video pass without making a comment. At about 3:00, the nameless person talking on the video calls the tornado as an EF-4. Nope, the EF scale is a damage scale. Anyone saying that a tornado is of any given intensity before a damage survey is done is being ... well, why don't I be charitable and say anyone who does so is being disingenuous. In other words, don't do it, as it's not valid.
A rewarding but frustrating day! As Dave mentioned, we (COD) got in muddy/wet roads and downned power lines. Even so, the position we were in, I don't think we could have seen the wedge. We did see the first tornado (white stovepipe/cone) that downed the powerlines though. We had to go south in order to reposition after getting to the power lines, but the view from behind near the RFD (which was warm) we had of that massive wall cloud was incredible. The cascading motion was amazing. We did get back into position near Roscoe, but not into the position we liked...near the hook. The inflow jets were very strong, rocking the vans pretty good. It was a very dangerous HP supercell to say the least at that point. All in all this was a great trip with 5 supercells, 6 tornadoes, good food, and new friends. I can't wait to get back to Red Deer!
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