


Severe Storm Outlook Narrative (AC)
Issued by NWS
Issued by NWS
897 ACUS03 KWNS 260742 SWODY3 SPC AC 260741 Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0241 AM CDT Sat Apr 26 2025 Valid 281200Z - 291200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS FROM CENTRAL IOWA INTO SOUTHEAST MINNESOTA AND WESTERN WISCONSIN... ...SUMMARY... An outbreak of severe weather is likely across portions of the Midwest and Upper Midwest. Large hail, severe wind gusts, and strong to intense tornadoes are likely. ...A tornado outbreak with the potential for strong to intense tornadoes is possible on Monday... ...Midwest into the Upper Midwest... A strong mid-level jet streak will move rapidly northeastward from the Southwest to the Upper Midwest on Monday. As this occurs, a surface low will deepen and move from the northern Plains to the northern Great Lakes. Strong southwesterly lower tropospheric flow will advect high theta-e air northward across the Midwest and into parts of the Upper Midwest. Broken to scattered cloud cover will support surface heating and strong destabilization across the warm sector in Iowa and into southeast Minnesota and western Wisconsin. Severe storms may develop as early as mid-day across western Minnesota and western Iowa on the nose of a 70-80 knot mid-level jet streak. These storms may begin as supercells, but mode may become more linear as the cold front intersects the dryline across Minnesota during the afternoon. Even if mode is more linear, embedded tornadoes will be possible given the strengthening low-level shear. Farther south and east, a more discrete mode will be favored within a weakly capped warm sector. As lower tropospheric flow strengthens through the day, the warm sector will expand rapidly northeastward, creating a broad warm-sector featuring moderate to strong instability and very strong (60+ knots) shear. Increasing forcing during the afternoon should be sufficient to overcome weak capping across the warm sector. Therefore open warm sector supercells will be possible in addition to supercells along the eastward advancing dryline. Any supercells which can develop within this increasingly favorable environment Monday afternoon/evening will be capable of strong to intense tornadoes. By late evening, a squall line will likely overtake much of the discrete convection as the cold front advances rapidly southeast. Severe wind gusts and embedded tornadoes will remain possible through the late evening and perhaps into the overnight hours. ...Central/Southern Plains... A strongly unstable and strongly sheared warm sector will exist along and east of the dryline from eastern Kansas southward to West Texas. Forcing is much weaker than farther north with only weak height falls along the dryline. However, most guidance shows minimal inhibition along the dryline and at least isolated storm development, perhaps aided by some nocturnal low-level jet increase during the evening. Any supercells which develop will pose a threat for all severe hazards including the potential for strong tornadoes. ..Bentley.. 04/26/2025 $$