Good Afternoon! Here are your latest updates:
Over the last 24 hours the majority of the region has seen scattered storms, but a system of storms moved through northern-eastern Minnesota overnight and into this morning that brought 3+” of rain to a broad region of the state.
Past 24 hour Precipitation totals:
Upper-level energy moving through the area this evening will spark more widespread showers and thunderstorms both tonight and tomorrow night. The storms that move through this evening will be slow-moving meaning they can cause heavy precipitation to fall over a short period of time throughout the majority of South Dakota and Southern Minnesota this evening. There will also be enough low-level energy to support isolated severe storms. The main risks associated with these storms will be large hail and strong winds, but there will be the chance of an isolated tornado with enough turning of the winds in the low-levels to support funnel development. The severe risk should subside as we move into the overnight hours and tomorrow morning, but will return once again Monday evening when the low-level energy builds back up again (this happens because of the daytime heating).
Modeled upper-level energy this afternoon through Monday evening:
Model simulated available low-level energy available for these storms this evening (anything yellow or greater is sufficient for severe storm development):
Monday evening will also feature a severe storm risk with the primary risks being strong winds and isolated hail pockets. There will be the risk again of isolated tornadoes with plenty of low-level spin being predicted by the models in the lower atmosphere.
Model simulated low-level energy Monday evening:
Greatest risk of severe weather through tomorrow evening:
Along with the risk of severe weather there is a risk for flash flooding as well. There will be plenty of moisture in the atmosphere to cause torrential downpours that could bring most of South Dakota and Southern Minnesota 0.5-1″ of rain this evening with isolated pockets of 2+” of rainfall if your area gets stuck under one of the heavier slow-moving cells. The models are even predicting an isolated pocket or two of 4+” of rainfall this evening. They are moving so slowly because the winds are turning as you go up in the atmosphere so the winds at the different levels are working to slow these storms down allowing them to pour down heavy rain longer. The greatest risk of flash flooding will be where you see those purples, yellows, and pinks on the maps below. Those areas could get 1.5+” of rain within a very short amount of time.
How much rain we need in a 3 hour period to get flash flooding:
Available moisture to fall as rain with these storms tonight:
Available moisture for storms Monday evening:
Model simulated precipitation accumulation through Monday evening:
Risk for flash flooding tonight (yellow is slight risk, green is moderate):
Risk for flash flooding Monday night:
Model simulated radar through Monday evening:
As always if you have any questions or concerns don’t hesitate to reach out! Have a wonderful evening!