June 19th had tornado written all over it. It didn’t disappoint either! Fantastic wind shear, high CAPE, good moisture for the high plains and upslope flow into the foothills provided all the ingredients needed to get tornadic supercells to form. An amazing sight, 3 significant supercell storms formed at the same time, situated about 50 miles apart. Usually the tail end storm is the cell you want to target, however, an old outflow boundary existed in which the middle cell developed on. It would be that cell that would go on to have amazing structure and produce the Prospect Valley tornado. All 3 storms would become tornado warned during their lifespans. The middle storm we watched grow from a smaller storm to a well structured tornadic supercell as it crossed I-25 and moved eastward. Various wall clouds, each time showing rotation, formed until finally rotation tightened to produce a tornado. A long snaking tornado was on the ground for nearly 10 minutes before roping out. After the tornado, the storm still spun as it moved across eastern Colorado before dying south of Ft Morgan. At that time, we blasted south to Limon and points east as the tail end storm took over the show. It also was tornado warned and may have produced a rain wrapped tornado north of Genoa. Structure was beautiful HP supercell, and it also was highly electrified. By early evening the storms lined out as they moved into Kansas producing high winds and heavy rain. A fantastic day for the tours as nature gave us quite a show!
Days like June 18th don’t happen very often. With good moisture, shear and instability, it was a pretty good bet supercells would form. However, we didn’t anticipate the shear number of supercells that would actually form! A boundary laying east/west across the northern Denver metro area extending into northeast Colorado would provide the needed focus for storm development. One supercell after another formed and tracked along the boundary. Every different type and structure of storm occurred and made for a photographer’s delight! Sculpted updrafts with good lightning, wall clouds, colors, possible tornadoes, and hail happened! Storms would rage on through the late evening hours before diminishing just before midnight. SLT co-owner Caryn Hill’s intercept of the Roggen, Colorado storm superseded the structure shot she got from the night before near Otis, Colorado! Absolutely stunning sunset supercell! Please enjoy the photos! They were gorgeous!
We expected a good day this day in South Dakota! Great instability, near 70 dewpoints, good shear and a dryline/outflow boundary intersection would set the stage for intense supercells late in the afternoon. By mid afternoon, a cluster of congestus formed in northwest South Dakota south of Buffalo. Soon several cells tried initiating there, with one dominant storm taking over the show. It quickly grew to 60,000 feet tall and became severe warned. Structure was decent and a wall cloud, complete with clear slot formed as it became tornado warned. This cell would weaken and intensify several times, but it never seemed a major threat to produce tornadoes. The tornado warning on the supercell continued for several hours, as broad cyclonic rotation occurred. It just never seemed like the rotation tightened enough to produce more than a weak funnel or two. By early evening, the storm lined out with a really pretty shelf cloud that had embedded mesocyclones that also became tornado warned. Still, a fun day, giving us many hours of chasing time on this pretty storm!
May 29th took us to northern Oklahoma. An outflow boundary and advancing cold front across Kansas would provide the focus for supercell thunderstorms this day. Good moisture and extreme instability, as well as good wind shear would provide the ingredients needed for storms to sustain themselves and be intense. The first supercell formed over northern Oklahoma west of Alva and become severe. Later it would be tornado warned and produce a weak tornado. The structure was quite pretty and the storm exhibited decent rotation from time to time. However it could not focus in one spot and usually had broad rotation. Nonetheless, it was a good long lived supercell and provided us many photographic opportunities along the way for Tour 5 and the Photo Tour #2! Enjoy the pics!
The end of April took us to the Texas panhandle for storms. The season has not even started yet due to persistent continental polar airmass intrusions, pushing surface moisture into the gulf of Mexico. Finally, we have a few days where moisture is returning, albeit slowly! With dew points in the 40s and 50s, storms during this two day period were high based, but marginally severe, producing large hail and high winds. Storms clustered along the dry line occasionally having supercellular appearances, however due to limited moisture, the tornado threat was zero. Enjoy the pics!
July 17th was a high plains upslope set up. Southeast winds along a boundary would funnel moisture into the Cheyenne ridge. A supercell formed early afternoon near Chugwater, WY and would right turn and track down the boundary into northeast Colorado. This storm was outflow dominant most of its life cycle and was a major hail producer. In Colorado it became tornado warned, although not a big threat in my opinion since it was outflow dominant. We came across some beautiful landscapes to photograph the storm, and everyone had a great time with it. The storm never produced a tornado but it did produce significant hail the size of baseballs along its path. This was to be the last great day for the season as we wrapped up tours and headed home to Denver. Thank you all for a wonderful tour season. We have the best guests and guides on the planet!
July 10th was day one for the Great North Tornado Hunt. A strong area of low pressure over southern Montana and an associated warm front extending east of there would provide the lift to produce numerous storms, including a few supercells. We intercepted the only tornado warned supercell in the country near Baker, Montana and followed it eastward along the boundary as it spun wildly. A few of times it appeared to produce a couple of funnels and even a brief dirt swirl under one, but the story with this beast was the pretty structure and amazing green colors. This supercell produced very large baseball sized hail and had long inflow bands eastward from the updraft. The open prairieland of eastern Montana always gives a great foreground for one of nature’s most violent storms, the supercell. A fun way to start off the final tour of the year!
The first day of the Reunion tour provided a decent high plains set up. Upslope flow into western Nebraska would push 60 dewpoints along a boundary as moderate westerly mid level winds would help generate enough wind shear for supercells. Two such storms formed along the northwest/southeast oriented boundary and would produce giant hail to softball size. Both supercells were tornado warned with the second storm producing a confirmed tornado near Eckley, Colorado. Structure was decent as well. We came back through the area the next day to find thousands of acres of cropland shredded to the ground, mostly corn. Sometimes hailstorms can produce more significant damage than a tornado can. This was the case with these storms.
June 5th continued the extended period of low severe weather potential across the United States. However, we always do everything we can to get our guests a storm of any kind! June 5th looked like a good day for storms in the Alamosa/Great Sand Dunes NP area. So off we went. By mid afternoon storms formed over the mountains and some slid off the mountains into the valleys below. It just so happened to be in a very scenic area in the Great Sand Dunes park. When there’s not much of a chance of severe storms we like to take our guests to scenic areas, with this area being quite pretty. Storms rolled over the dunes and produce heavy rain, lightning, wind and small hail. All in all it made for a pretty satisfying day, with a nice Mexican dinner in Alamosa to follow.
June 1st continued the streak of limited moisture and shear for the US. We decided to chase the Davis mountains in southwest Texas and were treated to a pretty storm with very large hail to tennisball size. Two supercells emerged from the mountains with one storm in particular becoming a prolific hail producer. It tracked from near Marathon eastward to Sanderson where it dropped its largest stones of the day, measured 2.5″ in diameter. Later on, the storm gusted out and outflow kicked up a cluster of new cells on the Mexico border that were producing an incredible amount of lightning strikes. Pretty indeed, and a great way to finish the day!