I just managed to see a supercell pass by to the south of Edmonton this evening. At 7:00 pm, I decided to check out one of the storms closest to the city, so I had to walk to the edge of the river valley, as I live in an area of highrises (obviously NOT good for stormspotting!) but the view from the river valley's edge to the SW, S and SE is great for observing approaching storms. At first, the mesocyclone was some 50 km distant and I could just barely make out the meso due to water vapour/smog haze. But the structure gradually became more visible as it got closer. It looked like the storm was falling apart at first, but managed to reorganize as it approached. The RFB in the meso didn't appear to have precipitation underneath, hence it was a classic supercell.
The meso had a very well defined "bell" or "cow-catcher" shape to it with some striations resembling somewhat what you'd find on a soft-serve ice cream and from time to time short, stubby inflow bands could be seen to the right. A high-based midlevel cloud platform sat just above the meso, and most of the upper half of the updraft was obscured by intervening clouds. A fairly long inflow band formed within about 2-3 minutes at one point. The supercell didn't seem to be very electrified compared to the dazzling lightshow of last night's thunderstorm, but it was putting out large CGs every several minutes immediately to the right of the meso.
Under the meso, I could sometimes see what looked like a wall cloud, but the thing was too distant for me to tell clearly. I was able to watch the storm for about a little over an hour, and it was apparently beginning to die out in the end, the meso becoming half-hidden by the rain curtain. The meso was about 20-30 km away at its closest to where I was, and it never rained more than a drop or two on me the whole tiime. Large, fat mammatus clouds were appearing on the anvil base.
