Chase Log: July 14th, 2003

Click on any of the SPC products below (Convective Outlooks, Watches, or MCDs) to see the SPC's "Severe Thunderstorm Events" page pertaining to this event.

MAP

Total Distance: 500 miles
Target Area: Spirit Lake, IA
Chase Area: Lake Crystal to Owatonna, MN
Maximum SPC Risk category: Moderate
Watches: Tornado Watches 744, 745, 746, 747, and 748
Mesoscale Discussions (MCDs): 1833, 1834, 1835, 1837, 1838, 1839, 1843, 1844, 1845, 1846, 1848, and 1849

I Spent a couple of days looking forward to this one. For the first time in a little while, there was an area of strong instability juxtaposed with very strong shear. Unlike the past several events, it seemed as though winds at all levels were to be quite strong for this time of year, and CAPE was to nicely overlap some of the stronger low-level shear. An approaching cold front, prefrontal trough, mid-level shortwave trough, and outflow boundaries were expected to provide enough sources for lift to initiate thunderstorms across southern MN and IA by mid-afternoon.

Well, this go to show that things never go as expected. I arrived in Jackson, MN, by about 2:30pm, at which time I grabbed a bite to eat, filled up with gas, and waited for the 3pm SPC Outlook to arrive. General thinking by surrounding NWS offices seemed to indicate that thunderstorms were expected to fire along the prefrontal trough around 21z. Surface winds across most of IA and southern MN were backed to the southeasterly direction, with a nice southwesterly 850mb jet and strong 700mb winds overlaying this. Temperatures and dewpoints were in the upper 80s to low 90s and low-upper 70s, respectively. I sat around Jackson, MN, for the most part, although I did wander into the Storm Lake, IA, area for a short time. For some reason, I couldn't connect to the internet down there, so I popped back into the MN area, where I was able to connect. At any rate, SPC issued a tornado watch by around 21z, and I was ready to roll.

Nope. Well, I was ready to roll, but the atmosphere sure wasn't. I sat and sat and sat around some more, waiting for anythign to happen. Nope. A strong cap (stronger than all models had forecast) overspread much of western IA and southwestern Minnesota. This meant that that awesome tornadic environment in the immediate area (central IA had 0-3K EHI of +12 --> +5500 CAPE with +300 0-3km helicity) was not going to be realized, despite very strong moisture convergence along the prefrontral trough. Darn. I headed west toward Worthington by 5:30pm, but quickly turned back around when I noticed the southwesterly winds. My hopes finally began to perk as cumulus congentus towers seemed to finally be able to take root, for a short time at least. By 6:30, I was hearing word of a nice tornadic supercell southwest of New Ulm, near the Sleepy Eye area. Oddly enough, when I was heading back from Worthington about 30 minutes earlier, I actually started driving northward towards that storm, but when I noticed the sloppy radar presentation of the storm, I decided to ditch it and stick with my original target area.

It had come to decision time: do I stay in my target area, or do I leave to go north for the storms near New Ulm. I decided that the cap was playing games again and that it was better to get something at least than to sit under partly cloudy skies in a capped environment. So, I headed north on Hwy 169, then west on Hwy 15, towards Lake Crystal. I was quite disappointed when I reached Lake Crystal (a small town just south of Mankato), for the storm was not looking very impressive. As I was heading north through town, however, a very low wall cloud rapidly developed just northeast of the area. All in all, it took about 2 minutes to go from no apparent lowering or rotation, to a very low, rapidly rotating wall cloud. I jetted east on Hwy 15 to get in line with the new, awesome wallcloud. But a couple of minutes later, rotation was seen at the surface and a tornado was occurring! Woohoo! I continued east on Hwy 15, with the tornado to the immediate north of the road. Because of my close proximity to the tornado, I was able to see intense and violent rotation with the beautiful tornado. It was on the ground for a couple of minutes perhaps (I lose track of time in situations like these.. :) ) The tornado then lifted just as I was putzing around with my map to find another road east, since my Hwy 15 had just ended. After some backroad manuevering, I was back in business. The low wallcloud and rapid rotation persisted throughout this time. Soon again, the wallcloud consolidated again and a tornado touched down.

Unfortunately, my memory is failing me again as I cannot remember how for west of St. Clair this was. At any rate, it is worth mentioning that as I approached St. Clair, the strong rotation (with extreme RFD winds... wow!) was no more than 1/4 mile north of my position. Speaking of the RFD, I was going east at 60-65mph at this time, and leaves and small debris were still passing me, going the same direction. Needing some film, I had to stop at a small gas station in St. Clair. Upon leaving town, I quickly regained a nice position and view of the wallcloud. By this time, it was becoming apparent that this supercell was becoming more linear. Nonetheless, strong rotation persisted. As I approached Waseca, I did notice a small funnel cloud rapidly develop just (just just) north of me. I did not see any surface reflection of this, however, so I don't think it touched down.

To make an already too-long storm a little shorter, by the time I made it through Waseca, the sun was setting, and I could no longer make out any distinct low-level rotation. A quick call to my girlfriend let me know that this storm had filled in with a line to its north, and thus the tornadic potential was rapidly decreasing. With all of this in mind, and the fact that I had to work at 10pm (good thing I told 'em I'd be late a couple of days ago), I gave up chase.

So, what could have been a fantastic-day-gone-down-the-tubes had turned into just a fantastic day: 3 tornadoes in 2 hours. I got the closest view of a tornado that I have ever had, and I witnessed the most violent rotation and wind that I have ever seen! And best of all, no deaths or serious injuries were reported with these tornadoes. The damage was mostly confined to rural areas, not to minimize those rural areas that did receive damage. After all, it doesn't matter how many homes were damage or destroyed if yours was.

I have some level II radar data from this event, just click the image you want:

07-14-2003 Chase Video

Click the photo or description to view the video

Tornado east of Lake Crystal - 16.9MB