Saturday, May 5, 2012 — Southeast SD-Northeast NE

Synopsis

The culmination of a long series of fool's errands, with a distance and price worthy of being the grand finale.

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SPC Convective Outlooks

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SPC mesoanalysis at 00 UTC

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Full Account

Move along; nothing to see here. A decent trough was forecast to eject in a somewhat junky fashion across the northern Plains, with most of the good shear north of the warm sector. However, just enough overlap looked possible across SE SD into N NE that many chasers feared the possibilities if they stayed home. Bryan and I were among them, and hit the road around 8pm the night before. We made it to York around 2am to find most of the area motels booked, ending up in an $80 Comfort Inn room in which the A/C was non-functional. That should have been a sign, and it probably was, but we were too committed to this chase for it to matter much at that point.

My main concern all along had been the northward progress of the warm front. In my mind, it needed at least to straddle I-90 for a good chance at this chase proving worth its cost and time. The 00z model runs the night before were not particularly optimistic, but left open a window for destabilization across far SE SD. By morning, though, intense elevated convection had erupted across the eastern Dakotas. As it plowed eastward into MN as a formidable MCS, its cold pool could be seen on satellite radiating outward as a density current, including rearward. We arrived in Yankton at noon to cold fog, as the effective boundary had been driven S of the Missouri. We spent much of the day at the town library, where Brandon, Dan, and Matt Van Every joined the bust party by mid-afternoon. Free wi-fi and a head-scratching conversation with a local religious zealot (who alternated between clearly-imagined tornado stories and trying to save our souls) were the day's highlights. By late afternoon, we meandered SW toward Bloomfield to watch failed convective attempts, finally conceding defeat an hour or so before sundown. We grabbed Subway in Columbus and pushed through the 6.5-hour drive home of shame, visions of Manchester no longer floating in our heads. The reality of late-season 2012 was setting in.