


Severe Storm Outlook Narrative (AC)
Issued by NWS
Issued by NWS
138 ACUS48 KWNS 240858 SWOD48 SPC AC 240857 Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0357 AM CDT Tue Jun 24 2025 Valid 271200Z - 021200Z ...DISCUSSION... Models are in good agreement with the overall pattern through Tuesday/D8, depicting a low-amplitude trough moving from the northwestern states on Friday/D4 across the northern tier of states and toward the Great Lakes by around Sunday/D6. This wave is then forecast to amplify across Ontario/Quebec through the end of the period, with cooler/more stable air pushing south with a cold front from the Midwest into the Northeast. Severe storms are currently forecast over parts of the Dakotas into northwest MN on Friday/D4 as the stronger flow aloft interacts with a moist and unstable air mass already in place. Damaging winds appear the most likely mode of severe, along with sporadic large hail as storms form during the afternoon within a surface trough, and beneath increasing winds aloft. While severe storms may also occur on Saturday/D5 over parts of the northern Plains or upper MS Valley, predictability is lower given expected storms the previous day and potential for long-lived convective systems. However, given such strong instability forecast on Saturday/D5, a risk area is likely to be issued in later outlook cycles over parts of the upper Midwest/MS Valley. Elsewhere, daily thunderstorms within the moist and unstable air mass are forecast for the bulk of CONUS from the Plains eastward, though in a generally weak shear environment. Portions of those areas may see low/marginal probabilities as the events enter into the Day 3 outlook time frame. ..Jewell.. 06/24/2025