June 25th and 26th took us across the border to chase in Alberta and Saskatchewan. The trip resulted in my first ever Canadian tornado intercept. On June 25th we intercepted an HP supercell near Kindersly that had an amazing sunset under the gusted out storm. June 26th was the day to remember. An outflow boundary set up from southwest to south central Saskatchewan and become the focus for intense supercell development by late afternoon. The storm struggled at first and then spun like a top producing 2 photogenic tornadoes, with the 2nd one less than a mile from us and very strong. Amazing surface obs feeding the storm (82/77 with east winds at 20 mph) helped the base lower and ingest every bit of energy available. Check out the photos below. The first photo is from June 25th sunset. The rest are of the tornadic supercell on the 26th.
June 22nd had some great potential. A warm front lay across the NE/SD border, with a dryline extending south from it. I have to admit, my target that day was the warm front/dry line intersection near Lusk, then eastward as storms could potentially ride the warm front. Indeed, the storm of the day did just that and we missed it due to the this being the final day of the tour and our tendency to lean south towards the Cheyenne ridge, which was also a viable target. We intercepted a supercell near Sidney, NE that rode eastward and became a very nice supercell. It produced a brief, 2 minute tornado, before becoming extremely photogenic.
June 12th featured good upslope flow into eastern New Mexico. Dewpoints in the 50s to near 60, CAPE to 3000 j/kg, good directional and speed shear, would set the stage for supercell development across that region. A cluster of supercells developed southwest of Hobbs, but we stayed put near Santa Rosa and were rewarded with a very pretty, nearly tornadic supercell. The storm was high based to begin, and then as evening approached and dew points also rose, the base came down and was tornado warned. The night time CG barrage was quite impressive as the updraft was lit up constantly.
June 7th was a tough choice. We agonized between the Platte river valley north of Chugwater or the Palmer Divide. Since we started in Denver, we chose the Palmer Divide. Of course, by mid afternoon a VERY nice tornado and supercell occurred in the northern target, which made us even more ill. Finally towers and eventual storms went up on the Palmer just southwest of Deer Trail. This storm intensified and right turned moving due south. It did produce several tornadoes, most of which were brief or rain wrapped (as seen below!). It also produced softball sized hail and intense lightning.
June 6th was an interesting day. I didn’t feel all the ingredients were present to the extend needed for strong supercells. Moisture was a bit marginal with temp/dew point spreads near 25 degrees. By late afternoon, the Palmer Divide lit up. An intense supercell eventually formed northeast of Elizabeth. This storm was nearly anchored in the upslope flow and produced copious amounts of hail to baseball size and nearly a half foot of rain. As it back built to the southwest, just northeast of Elizabeth it produced a substantial cone/elephant trunk tornado that was on the ground for 10 minutes. Fun storm to watch and even better when the tornado stays in open terrain and does not cause much damage.
What a day June 5th turned out to be! We were anticipating intense supercells to form and they indeed did. A strongly worded tornado watch was issued for central and northern Montana by mid afternoon, with shear, instability and moisture giving the potential for strong tornadoes. Several storms formed off the higher terrain south Great Falls. As they moved north, cool and stable air banked against the mountains would cause these cells to weaken. Another cluster of storms formed in the Judith Basin area and congealed into one monster supercell. This storm had insane structure and produced about a 12 minute elephant trunk/cone tornado. It produced another tornado northeast of Ft Benson we couldn’t catch up to due to poor road options. We also got pelted with near baseball sized hail in the notch of this beast as it raced northward. Another gorgeous storm!
June 4th took us to central Montana. Great flow with a shortwave moving into the Pacific Northwest would help set the stage for storm formation. Ample shear, good instability and moisture, and convergence along the mountains southwest of Great Falls would allow storms for form by late afternoon. A tornado watch was issued for the area as storms formed and intensified near Helena. One supercell moved towards Great Falls and became quite photogenic as it moved northeast towards Ft Benson. This storm became tornado warned and also produced baseball sized hail. One of the prettiest supercells of the year!