Chase Accounts

December 4, 1999
Pictures from this day.

Quite a dynamic system was forecasted to be moving through the North Texas area during the early morning hours of December 4th. Southeast winds at the surface progressively turning to west-southwest at 300mb would be enough directional shear to possibly produce supercells and tornadoes. Near the I-35 corridor, moisture was expected to be enough to fire some storms along a cold front that was to be moving through the area. SPC had the area under a slight risk, and the NWSFO in Dallas/Fort Worth was calling for supercells in the early morning hours and a few tornadoes. I took off work at 2 p.m. on Friday in order to get ready for the coming chase day. I got home checked some data and called Scott to see what his plans were. We decided that I would meet him at his college, the University of Louisiana at Monroe. At 3:15, I left Conway and made my way towards Monroe. After driving through some pockets of very heavy rain, I arrived at Scott's at 7 p.m. An hour later, we departed from Monroe to set up near Gainesville, TX. As we started to get closer to our target area, a severe thunderstorm watch box was issued for the North TX. area at 11:50 p.m. In addition to the watch box, the SPC was calling for a few tornadoes. The NWSFO was really playing this up big, as spotter activation was being expected, and they were calling for tornadoes to be likely. After we arrived at our target area at 1:30 a.m., we noted very strong southerly winds bringing the moisture in. From there, we waited to see any signs of convective activity. We saw our first signs of lightning at around 2:50 a.m., and the activity looked to be well west of I-35 at the moment. As we headed west, we were finally able to see the lightning illuminating some of the storm structure. About this time, the storms seemed to finally be blowing up along the front as the lightning became more numerous. Scott and I decided to try and get some lightning photos out of this activity, but, unfortunately, mine didn't turn out very well. Not long after, we started noticing some light precip beginning to fall. The main convective activity was still west of us, so we decided to find a hotel and get a good look at the radar to see what was going on. A thin band of showers had developed ahead of the main activity, and this would pretty much ruin our chances at getting anymore decent lightning photos. Also, the convective activity that was supposed to rapidly develop into supercells still looked very disorganized. Although, the NOAA was telling us that severe weather wasn't expected east of I-35 until daybreak, so we kept our hopes up. As it got closer to daybreak, we kept going east to stay ahead of the line of storms, and still, nothing was happening. This certainly was not looking good for our supposed early morning tornado outbreak. Also, the Hazardous Weather Outlook for the area was no longer being broadcast on the NOAA. Both Scott and I were getting very tired at this point, but we decided to push eastward towards the north TX, north LA. border in hopes that severe weather would blow up along the cold front once some daytime heating took effect. At 11 a.m. the next Severe Thunderstorm Watch was issued, and it covered parts of NE TX, NW LA., SE OK., and SW AR. While we were near Longview, TX.,on I-20, we finally started seeing some anvils off to our west. We decided to drive toward the line of storms that was developing to try and get a good view as to what was going on. As we got closer, the convection looked very mushy, and the anvils were very wispy and strange looking. All we saw out of this was a weak gust front and a lot of precip near Tyler at 1 p.m. As we made our way back east and moved out of the precip, Scott noticed a good looking storm off to our northeast that was showing signs of supercellular storm structure. At 2 p.m., a tornado warning for Cass county was issued for this same storm. Unfortunately, this storm was going to be too far away for us to attempt an intercept. The storms were moving rapidly to the northeast, and there was no way we were going to be able to catch it. We continued east along I-20 in hopes to catch a decent storm blowing up near us. While doing this, a couple of storms off to our NE had really gotten going and produced some mammatus for us to get a few photos of. While nearing Shreveport, finally, a Severe Thunderstorm Warning was issued for Harrison County at the TX./LA. border. We decided to get set up for this storm, as it was very near us. Scott was watching the TV at this time and got a good look at a radar image. He noted that the radial velocity image showed a strong rotational couplet, and at 3:10, a Tornado Warning was issued for our storm. We hit I-20 and made our way towards Marshall, TX, where the storm was expected to hit within a few minutes. This was a bookend vortice on the northern edge of a broken squall line. If there was a tornado, it would surely be wrapped in rain, but we had just enough time to intercept this storm as it crossed I-20. At 3:30, we began to see a lowering as we neared the Marshall exit on I-20. The lowering had a sharp point extending down and towards the south. I'm not sure if this was a funnel or just some inflow into the mesocyclone, but it was interesting, nonetheless. As we got closer, we slowed to a stop and watched what was going on for a couple of minutes. Very heavy rain curtains looked to be slightly rotating around the main area of concern. If we were going to see anything, we were going to have to get very close and get a look at what was going on behind the shroud of precip. As we made our way into the heavy rain, it suddenly slacked off, and we could see what was going on. An enormous piece of scud was being stretched and rotated into the mesocyclone. This was an amazing and eerie sight, as this may very well have been scud that was left from a dissipated tornado. Now, here's the problem with chasing on the freeway. We couldn't easily turn around, and we didn't want to sit around and let the mesocyclone pass right over the top of us. It appeared to be weakening rapidly, so continued west on the freeway, passing just below the edge of the meso, until we found the nearest exit. We quickly got back on the freeway and headed back east. As we neared the same area, we once again slowed, and noticed that the rotation was no longer apparent, but scud was still being rapidly lifted into the area. Once again, we passed along the edge of the updraft area and continued east. It wasn't until the next day, that I found out that a 140 yard wide F-1 rated tornado had touched down at 3:20 p.m. on the southwest side of Marshall and tracked 1.6 miles. That was the mesocyclone that we were seeing at 3:30, and I'm convinced that all the scud we were seeing was what was left of the tornado after it had dissipated. Because of all the obscuring rain, it probably would've been hard to see even if we had been there a few minutes earlier. As we continued east towards Shreveport, a Tornado Watch was issued by the SPC covering parts of northern LA, central AR., and western AR. Three other tornadoes in AR. and suddenly backing winds had prompted the SPC to issue this next watch as a Tornado Watch. Scott and I certainly weren't expecting to hear that, and we had to decide if we wanted keep chasing into the night. It would be getting dark within the hour, and Scott and I weren't convinced of the chance of tornadoes after sunset. It had already been a very long day, and we ultimately decided to end the chase at dark. From there, I dropped Scott back off at ULM, and I proceeded home for a long rest. While I was on my way home, I encountered the squall line again near Monticello. Time was around 8:30, and at this point, it had only turned into a heavy rain producer. I didn't even see a trace of lightning associated with it. I finally arrived home near 11 p.m. after adding 1500 extra miles to my car. It was quite an up and down day, but one that ultimately turned into an enjoyable chase day.

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