The summer of storms here in 2010 kept on giving spotters and chasers treats yesterday. According to the forecasts from a day earlier, yesterday was supposed to be a rainy, but otherwise non-descript day in our area. A low pressure system was forecasted to go to our south, taking its instability with it and leaving my area with a day of moderate to possibly heavy rain. But as the day progressed, the low migrated further north than expected and the Storm Prediction Center put my area in a risk for severe storms. The low did not disappoint.
I spotted two storms, one virtually right next to each other with only about 5 miles between their edges. Both storms skirted Mankato, one to the east and the other to the west, and followed parallel paths towards the northeast. Storm 1, the storm that passed to the east, was photogenic because it had an ominous-looking shelf cloud out front followed by incredibly heavy rain. Here are two pictures taken about 5 minutes apart. Both are looking southeast.
I was not in an area that allowed me to see the updraft for this storm. From my perspective, the updraft, where the really nasty, but photogenic, stuff would happen, is to the right of this picture and obscured by rain. I didn't get in a better position because the other storm that I chosen to spot had developed a small hook echo observable on the radar. So I traveled about 5 miles north and west and got in position as the storm came over the Minnesota River valley.
By the time I got into position, Storm 2 had crossed into the river valley and had developed the "mothership" appearance and an obvious wall cloud.
The storm was too close to me at this point to entirely fit in the viewfinder. The image above is looking due west and the following picture is looking south-southwest.
I fully expected to see ET whipping out his iPhone to phone home as the mothership approached. I even thought I saw Richard Dreyfuss hiding in the trees behind me. The pictures don't do this storm justice: this was an incredible-looking storm to behold.
When the storm passed due north of my position, I was about a quarter mile or less away from the wall cloud. Here's what the wall cloud looked like as it passed by.
The wall cloud soon dissipated, but a new one grew almost immediately as the storm moved off to the northeast.
Soon after I took this picture, the NWS issued a tornado warning for the area in its path. I was sort of surprised to hear the sirens because while it had an obvious wall cloud, there was no obvious sign of rotation to me. I tried to follow it as it scurried away, but it seemed to pick up speed and I was running low on gas. So I let it go. What cowards these storms are. They come and freak people out and then run away.
*I use the word "treats" because to my knowledge, there was no damage done anywhere in our area although there were a few reports of severe hail.