Chase Logs 2009
The Wait is Over: First Minnesota Tornadoes of 2009
June 17, 2009
3:00pm-11:30pm
Anoka, MNI've been itching to write my first chase log of the season for a loooong time, but the lack of severe weather this season has been nothing short of depressing. After months of camping out under a cool, dry Canadian air mass, the jet stream finally rocketed northward today and brought with it our first humid and sticky day of the year. The SPC included most of western and southern Minnesota in a slight risk for today with a 5% tornado probability polygon encompassing the southwestern corner of the state. The first round of storms actually fired west of Breckenridge, MN and slowly drifted eastward across the Red River. While its footprint on the radar scope was minute, strong low-level wind shear (and subsequently high helicity values) meant that it wouldn't take much for any storm to become tornadic. Sure enough, the storm began rotating and dropped at least one (possibly two) brief tornado in southern Wilkin County. This was the first tornado of 2009 in Minnesota, the latest first tornado of the year in the state since 1952 and ranks only behind 1951 (June 19) and 1952 (June 23).
But, as usual, Mother Nature decided that this wasn't enough. A second round of storms exploded north and west of Albert Lea shortly after 6:00pm along a moisture axis, which was subsequently the most volatile region around with SBCABE over 5000J/kg and helicity values over 400 m^2/s^2. Tornado warnings ensued before 7:00pm as other cells cropped up south and east of Mankato. The cells tracked southeastward throughout the evening and dropped numerous tornadoes across southeastern MN and northern IA. One tornado in particular appears to have caused significant damage and injuries around the north side of Austin, MN. More information will surely be available by tomorrow morning. Currently the two remaining storms appears to be merging and bowing out over far SE MN, but the threat for an isolated tornado does still exist for the next hour or so before the storms become completely linear. While Anoka remained displaced from the action today, I biked over to the high school and shot some photos of a nice crepuscular ray display and the dark but hazy skies to the south (photos below)--all while watching a high school baseball game :).
Nocturnal storms sprouted suddenly at 10:00pm CDT near the Chanhassen radar near the intersection of the surface moisture axis and a small shortwave. The thin line of storms quickly advected eastward and became severe at 10:30pm in the southeast metro. I ventured outside at 10:30pm and noticed that lightning flashes from the storm were bouncing off the haze to the southeast. I debated for awhile about whether I wanted to try shooting lightning photos since the bolts were so weak, but given the lackluster start to the season, I figured I had nothing to lose. I packed up the DSLR and the SX10 IS and drove to the high school parking lot. Sure enough, small bolts were jumping from the billowing cumulonimbus clouds to the southeast. But the best sight was the internal lightning bolts, which lit up the silhouette of the blooming CB cloud. Unfortunately, the low haze deck combined with nearby light pollution trashed my photo attempts (see photos below). I did also manage to take some video of the storm using the SX10 IS, which didn't turn out half bad (considering how the photos turned out). That video is posted below as well. The storms began drifting out of range at 11:30pm and I packed up my cameras and headed home.
