Convective Outlook
— Day 4-8
Day 4/Sat Ohio Valley ?
An upper trough will overspread the Great Lakes and Midwest on Saturday. At the surface, a cold front will sweep east across the region during the day. Destabilization will likely be limited by downstream cloud cover within a strong low-level warm advection regime ahead of the front. Additionally, convection will likely be ongoing in the vicinity of the front from Lower MI into IN/IL. Nevertheless, strong mid/upper flow (40-60 kt in the 850-700 mb layer) will support strong to severe convection even amid weak instability. As such, a damaging wind gust risk will accompany linear convection moving across the region during the day into evening.
Days 5 6/Sun Mon ?
Strong high pressure in the wake of the cold front from the Day 4 period will overspread much of the CONUS east of the Rockies early next week. A dry/stable airmass will preclude thunderstorm potential.
Days 7 8/Tue Wed ?
An upper trough is forecast to develop across the western U.S. Tuesday/Wednesday. This will result in lee trough development across the High Plains, and strengthening south/southeasterly low-level flow will transport Gulf moisture northward across the southern Plains. Medium range guidance varies on whether or not this western trough will eject into the Plains during this time, or if upper ridging will be maintained. If the trough ejects, severe potential could develop across portions of the southern/central Plains Tuesday/Wednesday, though predictability is too low at this time to introduce severe probabilities.
000 ACUS48 KWNS 150755 SWOD48 SPC AC 150753 Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0253 AM CDT Wed Apr 15 2026 Valid 181200Z - 231200Z ...DISCUSSION... ...Day 4/Sat - Ohio Valley... An upper trough will overspread the Great Lakes and Midwest on Saturday. At the surface, a cold front will sweep east across the region during the day. Destabilization will likely be limited by downstream cloud cover within a strong low-level warm advection regime ahead of the front. Additionally, convection will likely be ongoing in the vicinity of the front from Lower MI into IN/IL. Nevertheless, strong mid/upper flow (40-60 kt in the 850-700 mb layer) will support strong to severe convection even amid weak instability. As such, a damaging wind gust risk will accompany linear convection moving across the region during the day into evening. ...Days 5-6/Sun-Mon... Strong high pressure in the wake of the cold front from the Day 4 period will overspread much of the CONUS east of the Rockies early next week. A dry/stable airmass will preclude thunderstorm potential. ...Days 7-8/Tue-Wed... An upper trough is forecast to develop across the western U.S. Tuesday/Wednesday. This will result in lee trough development across the High Plains, and strengthening south/southeasterly low-level flow will transport Gulf moisture northward across the southern Plains. Medium range guidance varies on whether or not this western trough will eject into the Plains during this time, or if upper ridging will be maintained. If the trough ejects, severe potential could develop across portions of the southern/central Plains Tuesday/Wednesday, though predictability is too low at this time to introduce severe probabilities. ..Leitman.. 04/15/2026