Starting this thread due to the presence of a shortwave across the Dakotas that is currently kicking off storms, at least one of which is rotating (albeit, marginally), just northeast of Pierre, SD.
Discussion:
Storms are initiating along what appears to be a dryline associated with a sfc low created by said shortwave. The low level flow has really adjusted nicely to the height/pressure gradient with this shortwave, with plenty of > 20 kt 0-1 km shear across much of central SD. The southern portions of this dryline feature sufficient moisture and heating to provide 1000 - 2000 J/kg SBCAPE, although most of the current activity is closer to the 1000 contour. Deep layer shear is sufficient for supercells, as a broad area of > 40 kt effective bulk shear is currently in place across most of E SD and into parts of N NE and NW IA. It's possible that the mid-level speed max of > 50 kt Wly flow will work its way east from WY/MT over the area within the next few hours providing for even greater shear as diabatic cooling sets in and storms slowly become elevated. Wouldn't be surprised to see an MCS tracking across E SD/W MN and perhaps NW IA later this evening.
Discussion:
Storms are initiating along what appears to be a dryline associated with a sfc low created by said shortwave. The low level flow has really adjusted nicely to the height/pressure gradient with this shortwave, with plenty of > 20 kt 0-1 km shear across much of central SD. The southern portions of this dryline feature sufficient moisture and heating to provide 1000 - 2000 J/kg SBCAPE, although most of the current activity is closer to the 1000 contour. Deep layer shear is sufficient for supercells, as a broad area of > 40 kt effective bulk shear is currently in place across most of E SD and into parts of N NE and NW IA. It's possible that the mid-level speed max of > 50 kt Wly flow will work its way east from WY/MT over the area within the next few hours providing for even greater shear as diabatic cooling sets in and storms slowly become elevated. Wouldn't be surprised to see an MCS tracking across E SD/W MN and perhaps NW IA later this evening.
