Similarity with July 2, 1997 Outbreak

Weather data in 1953 was certainly quite sketchy for forecast and post-mortem purposes. Yet we can draw many comparisons to a similar tornado outbreak that occurred on July 2, 1997. On that day, a F3 intensity tornado occurred along a track just a few miles north of the 1953 Flint-Beecher tornado track. The similarities between the two cases are hard to ignore. On the morning of July 2, a strong 500 mb low (Figure 9) was present over the Minnesota "Arrowhead" with strong winds in excess of 50 knots just upstream over Wisconsin and Illinois. There was also plenty of mid-tropospheric dry air moving into the Great Lakes region at 700 mb (Figure 10), along with relatively warm temperatures at that level south of Michigan - thus suggesting a capping inversion to limit thunderstorm activity over Ohio and points south. At the surface (Figure 11), a low was also over northern Minnesota with a warm front moving northward through lower Michigan and an advancing cold front just west of Lake Michigan. Estimated CAPE values in this particular case were just shy of 4000 joules/kg over southern lower Michigan.

Using this case as an analog, we can perhaps have an idea of how the June 8, 1953 tornado outbreak may have appeared on radar and satellite. Figure 12 shows a water vapor image from 445 pm on July 2, 1997, showing thunderstorms occurring over southern lower Michigan, a significant amount of dry air to the immediate west, and a large upper level circulation over northern Minnesota. Radar imagery (Animation 1 and Figure 13) from 445 pm shows a series of supercell thunderstorms lined up ahead of a cold front in eastern lower Michigan. The supercell centered over Tuscola County at this time is producing a tornado in northern Genesee County near Clio, MI and is the "right-moving" storm following a storm split an hour earlier. The "left-moving" storm in this split is apparent over Saginaw Bay in this image. There is evidence that such a split may have occurred in the June 8, 1953 event as well.