Day 6 was supposed to be a good day. And it was. In south Dakota. D'oh!
We headed for SW Nebraska, as planned. Things were looking good: all the ingredients were in place and initiation was imminent.
Storms went up right where we figured and we were excited, at least until dewpoints started dropping.
Uh oh.
It turns out the moisture wasn't quite as deep as we had thought and thus mixed out. We had dewpoints near 20 that dropped to 15. Crap. So we ended up with a couple of supercells that never really had any chance at producing anything more than large hail.
North of the Black Hills in SD was a tornadofest. Slow-moving storm producing a bunch of tornadoes. Bleh. (This, along with the next day, was a main reason for my writing about the psychology of storm chasing.) We had had that sort of area as a secondary target but we seemed to get blinded to the downfalls of our forecast. Well, that and like I mentioned before, not knowing how deep the moisture was. A sounding from Dodge City, KS would have helped tremendously, but they're in the midst of changing their sounding systems. Seriously, who changes something like that smack dab in the middle of their severe weather season?
The next day, day 7, was the big day in IA, MN and ND. We shot to Sioux Falls, SD for lunch and to dig into the data. We recognized the northern target as awesome and realistically unreachable, so blew it off. There was a pretty good convergence line going NNW-SSE west of the twin cities, a pseudo warm front, so we headed for the intersection of the left exit of the jet (per WV) and that front. We figured tornadofest day 2 would be on tap.
Well, storms went up a bit north of the target and we figured they would slowly go southward along the line. They did go, but the ones in our area didn't go well. They struggled, whether it was with the cap or against shear or I don't know what. But they struggled. One storm then decided to get a lot meatier and we chased it for about 2 hours along scenic Minnesota roads lined with trees. At one point the rotation in the wall cloud was so rapid that Paul and I were both convinced it would produce. One stuck van later (we got it out in about 5 minutes) the storm started to lose its oomph. So we abandoned it and headed south to storms that we heard had produced prolifically in northern Iowa and southern Minnesota. We got there just in time for a major RFD surge and that was the end of that. Well, except near sunset where shelf clouds and rainbows played with the sunset and we got colours that were impossible to photograph and that I believe I will never see in nature again.
I have no regrets about this day because I still don't know why storms in far southern Minnesota ended up producing and ours didn't. Just no clue.
Yesterday (day 8) was another day with high hopes and we hit initiation along a combination outflow boundary/warm front in southwest Iowa. A morning MCS (that later smoked Chicago) was going through Ames with strong winds. Later in the day, we were
right there at initiation. But the storms just kept on gusting out. The side bonus to this non-tornadic day, though, was the pure awesomeness and number of shelf clouds. We got at least 5 wicked ones, starting at about 9 AM.
Today is another day kind of like yesterday. There was an overnight MCS in northern Kansas and its outflow and a warm front near the area will be the play. Midlevel flow looks good and so we're initially targeting York, NE. Keep your fingers crossed!
