Good evening everyone! Spectacular amounts of sunshine is being observed across a vast majority of the Dakotas into northwestern MN as of 4:15pm CDT. However, an area of clouds is working through portions of MN into far eastern SD with a couple areas of stray showers and storms persisting along the eastern SD/NE border and far northeastern MN. The convection along the SD/NE border is expected to continue fading over the next couple of hours while isolated showers and storms in northeastern MN will work out of the area.
We are eyeing the potential for a few strong storms capable of producing large hail across northern ND into far northwestern MN from very late evening through the morning hours Tuesday. This can be contributed to decent instability, high lapse rates, and strong vertical wind shear. While not a large threat, any storm that develops/tracks through this area may contain this threat along with gusty winds and/or a brief spin-up.
Here’s a general synopsis of what to expect going through the night and morning hours Tuesday: Energy working into the northern 2/3rds of ND this evening will bring the threat for scattered strong storms. This threat will push eastward through the night, impacting far northwestern MN during the morning hours Tuesday. It should be noted that the latest high-resolution model guidance from various models differ from one another, with some keeping most of the storm activity out of ND and into southern Canada. Due to energy and instability in the region, we favor the solution previously discussed, though lesser coverage can’t be ruled out. Isolated showers and storms are also expected to develop across far eastern SD into central MN after 6pm CDT this evening and persist across portions of MN during the overnight hours.
Simulated radar through 1pm CDT Tuesday: Isolated showers and storms develop in far eastern SD into central MN this evening, gradually pushing eastward through the overnight hours with a stray shower or storm possible in eastern MN during the morning hours Tuesday. Elsewhere, the pulse of energy works into the northern 2/3rds of ND late this evening bringing with it scattered showers and storms, possibly strong, through the overnight hours. By 7am CDT Tuesday, strong storms are expected to still be hanging around northeastern ND into far northwestern MN. This model depicts these storms weakening over far northern MN Tuesday morning, but given a strong low-level jet with increasing low-level moisture, we can’t rule out these storms persisting across far northern MN through the morning.
Tuesday afternoon and evening will bring an additional chance for strong storms, mainly across the eastern third of ND into northwestern MN. Storms in these areas may contain large hail, damaging winds and/or an isolated tornado given the dynamics at play.
Here’s a brief synopsis of the setup Tuesday afternoon and evening: The best chance for showers and storms at 7pm CDT Tuesday (time for graphic shown below) will be located across southwestern SD into eastern ND and northwestern MN where energy/forcing will be greatest. Isolated storms are possible elsewhere in the circled region. Given instability across SD, we cannot rule out an isolated strong storm with hail.
Simulated radar from 1pm CDT Tuesday through 7am CDT Wednesday: Showers and storms will develop along the cold front stretching from southwestern SD into northwestern MN, mainly after 4pm, while lifting ENE across SD and western/northern MN afterwards through the overnight hours into Wednesday. The best coverage will exit across far eastern ND into northern MN. Additional energy will work into western ND and northwestern SD with storm risks increasing in those areas during late nighttime/morning hours Wednesday. By 7am CDT Wednesday, areas of convection will continue across portions of MN, eastern SD, and ND.
Total rainfall through 7am CDT Wednesday: This model has the wettest solution of the high-resolution guidance, so we wanted to show you the possibilities of what might happen. Rainfall is likely overdone across far eastern SD into central MN, but where it rains in these areas can pick up 0.25-0.75″ at best. Localized pockets of 0.5-1.5″+ is possible in northern ND into northwestern MN where the greatest chances for rain/forcing will exist through this timespan.
If you have any questions do not hesitate to reach out! Have a great evening!