I had the chance to stay in Norman this summer, working for a National Severe Storms Lab scientist named Dr. MacGorman. The day-to-day part of my job is data retrieval, processing, and archiving for the Oklahoma lightning mapping array (LMA). The part you'd be interested in was a field project from May 15 to June 30, Deep Convective Clouds and Chemistry (DC3), which involved all kinds of government agencies and a lot of researchers from around the nation. The overall objectives dealt with how thunderstorms affect the chemistry of the troposphere, particularly how they transport substances from near the surface to the upper troposphere. Where Dr. MacGorman and our team came in was taking in situ measurements of thunderstorms via balloon, as mobile radar crews and specially instrumented aircraft sampled the storms simultaneously. We launched balloons that, when inflated, filled the back of a full-size U-Haul truck--which is exactly what we used to get them to launch sites. Attached to each balloon, at least at first, were a particle imager, an electric field meter, and a regular radiosonde that measured temperature and humidity, as well as tracking devices. As the project progressed, our balloons kept falling after reaching only 3-4 km into the atmosphere. Since we were shooting for several times that altitude, the instruments for our final few launches were split between two balloons, which then topped 20 km. Getting paid to chase storms was exhilarating, if sometimes exhausting, and I wouldn't trade the experience for anything. Here are the highlights.
May 19: DC3's first Oklahoma chase took us to the dryline in western/northwestern Oklahoma for high-based severe thunderstorms. We stopped at an intersection at Leedey as the young storms grew. The mobile mesonet (minivan with instruments on top) was my vehicle for most of the project.
We moved south to Moorewood to intercept and launch. Two launch sites were decided against before we wound up in an open field near a small oil or natural gas facility.
We launched successfully, though the balloon didn't reach its desired height. At Arapaho, after the launch, we were treated to spectacular mammatus.
May 25: After spending hours in an Altus, OK, gas station/Burger King, we ran down a left-moving severe storm near Erick. We launched amid a barrage of close CGs but the instrument train dropped off the balloon before reaching cloud base. A nice sunset was little consolation.
I spent the next week in Silver Spring, MD, at NOAA headquarters, for a scholarship orientation with three fellow rising juniors from the School of Meteorology. We missed the best chases of the summer.
June 3: Equipment failures made a trip to Memphis, TX, a total fiasco. No launch.
June 4: Paydirt in the middle of nowhere, roughly in the vicinity of Paducah, TX. This was after driving through high winds and blowing dust to reach the storms. We were surrounded by unsettlingly close CGs from launch time long into the night.
June 12: We blasted from Norman to Lubbock, TX, and immediately were in pursuit of supercells only a county away from the New Mexico border. All the storms were splitting, and we positioned ourselves to catch a split from the only storm that didn't. It left us in the dust, accelerating northward, and we proceeded to invade an IHOP near Texas Tech's campus. We stayed up through the wee hours of the morning on the 13th to intercept an MCS moving into the Lubbock area. It fell apart on top of us, yielding essentially no data, but letting us practice our new two-balloon procedure in driving cold rain. Here's mammatus from the storms near New Mexico, in Seagraves, TX.
June 16: It was one of several long, frustrating, and sometimes plain strange days wandering central Oklahoma in search of elusive pulse storms--ask me about the machete-waving motorcyclist in Binger sometime. Persistence paid off with our best intercept. We caught a severe storm just south of I-40 near Hydro, OK, and launched two balloons with lightning striking all around. It was the first time I thought we were in serious danger from lightning, as we stood on top of a hill at an oil or gas platform and watched rapid-fire CGs hit in a valley below us.
We punched through this storm on I-40 in search of bathrooms around Hydro. It was an intense experience to be piloting the mesonet. Later, at a crop duster airstrip roughly north of Alfalfa, OK, a few crew members had their hair stand on end with a couple very close lightning strikes from decaying storms. After the danger passed, the full arc of a double rainbow appeared.
At the tail end of DC3, Oklahoma was plunged back into the bone-dry oven that is summer in the Southern Plains. Norman went many weeks without receiving 0.1" of rain in a day. Wildfires ravaged central and northeastern parts of the state, including a large area just south of Lake Thunderbird. Flash forward to the last weekend of summer. August 18 finally brought rain to central Oklahoma in the form of two morning/early afternoon sub-severe MCSs. Here's the first one near Lexington, OK, and a roll cloud with the second one as it approaches OU's campus.
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