April 12, 2020

From my morning chasecast storm chasing forecast email discussion list:

"Day 1 Today: HRRR and RAP adamant that warm front will be suppressed and hang out to the south through much of the day. 12z NAM now on board with this solution, but still drags the warm sector way north into Tennessee in the evening. The south warm front looks realistic given the training line of storms now on the front and the huge plume of precip coming out of TX/LA that was forecast earlier. So your target may shift south accordingly.

Tornado potential looks maximized se of the effective triple point in central MS by mid to late afternoon where extreme effective SRH and moderate instability will yield an environment very favorable for tornadic supercells. Questions about and uncertainty on storm mode remain. I see a couple of possible chase plays here:

Target 1: extreme se AR, ne LA. There is a tornado warned line moving into LA now that has been ongoing overnight. It looks messy, but you might get a play off of Tail End Charlie.that may track near the LA/AR border and then into MS. I'd try to catch it in the floodplain there on the west side of the river and on a big highway if you can. This is an early show, say noon to 2pm? Worried about storm mode, and the Mesoanalysis RAP not showing much 0-3km CAPE up there, like the surface stays cool from all the ongoing precip. A narrow window to intercept too.

Target 2: Try to catch more mature supercells later in the afternoon in e central MS/nw AL. This complex will likely continue to track tornado warning up toward the Tupelo area. It may peak sw of there with the surface heating. Catch it up on I-22 or adjacent highways. HRRR consistently showing discrete initiation southwest of Tupelo. That's your ideal target. Anything discrete and surface based in the warm sector will likely produce given esrh values exceeding 500 across most of the warm sector.

So just hang out way downstream and head off one these fast moving cells at an open location like you're catching a line drive or playing pong. Tornado warnings already citing northeast motion at 60 mph. Expect to see even higher today as the jetstreak roars overhead. This is a point intercept, don't try to keep up. Have your escape route ready to go with a couple options so you can get out of the way as the cell approaches without crossing the apparent path of the tornadicor RFD region.

Stage in Tupelo and then intercept heading south or east southeast on I-22 toward Hamilton, AL.

You might get a round too as the whole line lights up by evening as well and races through MS/AL Just position north/south on a good hgihway for a dominant cell depending on where you wind up after Round 1.

Don't get your hopes up, and stay safe. There are going to be way better chases this year."

This was my first long distance chase since the Covid-19 pandemic began. I had made preparations to be totally self sufficient and have no human contact beyond that of the self serve gas pump. I packed days worth of food and water, and would be car camping. Sunday, April 12 looked like it could be a potential outbreak with a strongly sheared environment and moderate instability. I don't typically chase the Deep South due to the tree coverage, but it's possible to capture dramatic shots when you can catch a long duration tornado from an open area downstream. There was some anticipation this event would be upgraded to a High Risk by the Storm Prediction Center, but probabilities were kept at a Moderate. My initial target was up in the Tupelo, MS area but ongoing precipitation suppressed the northward extent of the warm sector. I dropped south of the Columbus area where parameters looked maximized, hoping I was far enough downstream so that I could let a mature tornadic supercell come to me, rather than making a futile effort to chase in the jungles.

Multiple areas were lighting up with tornado warnings and reports well to my west and southwest, but I chose to remain on the northeast side of the activity and wait. A line of storms was approaching. They looked fairly linear, but the radar suggested they had intense updrafts, and I know such storms can very rapidly organize when they hit an area of enhanced directional shear like a warm front. North of Brooksville, MS, I got my first tornado warning of the day under grey featureless skies yet prolific cloud to ground lightning. I could hear the town's tornado sirens in the distance over the sound of the rain on the car.

The storm track had the area of interest passing south of Brooksville. I dropped south into town to get closer, but then held my position a few miles to the north of the crossing location. The second warning issued cited a storm motion to the east at 60 mph, and the supercell was already in a high precipitation state. The storm's rear flank core would be miles wide and could be harboring a violent yet totally hidden tornado inside. Getting in front of such a beast, I could easily get run over with no time to clear the path. So I instead decided to play it safe and give the storm a wide berth, stopping when I had a visual on the occludsion.

A dark mass crossed the highway to my south, and whatever it was, it appeared in contact with the ground.

Powerflashes as the mass crossed the highway pretty much confirmed for me that I was looking at a rain wrapped tornado. I hoped visibility would improve on the back side of the circulation as it moved northeast away from me. But the tornado just became more and more rain wrapped.

I made a mostly vain effort to come in behind the tornado, slowed down for a few moments by stopped traffic and chasers. I thought I had a visual on the circulation off to my north for a few moments, but I couldn't get a clean shot of it. There was just too much rain in the rear flank. Then I hit a smattering of light debris where it had crossed.

I plotted my way back to highway 45 to get on a new storm. Google had fortunately already routed me around a closure on the highway where the Brooksville tornado had crossed. Unfortunately the back roads of my detour were flash flooding in the training line of cells. Running water flowed along both sides and was ponding in low intersections.

I made it back to the highway after fording a few tricky spots.

I headed south down 45 to catch something discrete coming up out of the Jackson area. One of the training cells had a pointy lowering that looked like it could be a funnel cloud, or it could have just been pointy scud forming in the rain cooled air of the gust front wake.

A tornado emergency was issued for Clark County, MS, rare, enhanced wording in the warning text that means a confirmed, violent tornado is impacting populated areas. I blasted south down to Meridian. I never want to see people impacted by these storms and hoped the circulation would remain over rural areas, but more than an hour out from the intercept, I also hoped this would be the big, long tracking wedge that would stay intact until I arrived. I went south out of Meridian on 45 instead of making for a more direct intercept on I-59. I feared I'd be risking a core punch on 59, and with a violent tornado in a possibly HP storm, I wasn't taking any chances. I dropped south out of Quitman. There was no view to the west except a blanket of low clouds streaming north northwest. I went back north and then back south, hunting for views and trying to hone my intercept of the storm track. The tornado emergency made me anxious as I waited for the black form of the beast to appear behind the treeline to the west. It never did, and I never had a visual on supercell structure beyond a couple vague gust fronts. The storm seemed to slow and turn left as it weakened.

I ran north up 45 when the left turn became obvious on the radar, but by then all I could find was another smattering of debris where the tornado had crossed.

Light was fading and the event was leaving me behind as storms tracked into Alabama, so I started to make for home. Along the way, I came up on the track of another rotating storm. It didn't have a tornado warning yet, but the velocity couplet and shape of a developing supercell were prominent.

I stopped on 45 and let the storm come to me. it soon picked up a tornado warning. I strained through the last of the twilight and over the trees to spot something under the base, but all I could see was a dark updraft with ragged scud feeding into it from the north.

I called the chase and headed for home, passing through the damage path of the Brooksville tornado. Crews were still working on an overturned semi in the southbound lanes. The rest of the drive home was pretty uneventful, and I car camped in a rest area parking lot without going inside. It was probably closed anyway.