Outlook:
Multiple rounds of severe storms are anticipated as a disturbance moves through an unstable airmass across the Greater Plains from this afternoon through the overnight hours. These storms will be capable of producing very large hail, destructive gusty winds, and a few tornadoes if conditions align. For detailed information on timing, impacts, and more, refer below.
Detailed Forecast Across the Greater Plains:
Today, an upper ridge will start over the northern High Plains but will flatten and move eastward as a shortwave trough moves across the northern Rockies. This change will cause a surface low-pressure system to deepen over eastern Montana during the day and move into the western Dakotas by evening. A cold front will push east across the region overnight, with a surface trough/dryline extending south from the low across the northern and central High Plains.
South/southeasterly winds will bring moist air with dewpoints in the low to mid 60s°F northward across Kansas, Nebraska, and into the Dakotas and eastern Montana. Cooling air aloft and steepening lapse rates (change in temperature with height) will create strong instability. The wind profiles suggest that supercells could form in the afternoon, especially at first before becoming more linear later on.