IEM Daily Feature
Monday, 05 June 2023

Meager Shear

Posted: 05 Jun 2023 05:30 AM

The weather to start off June has more resembled August with slow moving afternoon thunderstorms driven by a humid air mass and strong heating. The slow storm movement has even been in uncommon directions to the west and southwest. The reason is that the flow of air aloft is rather stagnant from the east and without much directional nor speed shear to support more robust thunderstorm activity. The featured chart presents a measure of speed sheer between the surface and 3km aloft based on an archive of soundings from Davenport. The units and concept here maybe a bit too meteorological, but generally higher shear values support more robust thunderstorms by allowing the updraft and downdraft of the storms to be separated. Otherwise you get pulsey behavior as the downdraft interferes with the updraft. Anyway, you can see how recent sounding values this year have been at the very low end of a climatological range.

Good = 13
Bad = 0

Tags:   sounding   shear