Convective Outlook
— Day 2
Slight Risk
Summary
Severe storms capable of large to very large hail, wind damage and perhaps a couple of tornadoes will be possible Saturday afternoon and evening across parts of the central Plains. Scattered thunderstorms will also pose potential for strong to severe winds across the lower to mid- Missouri Valley.
Synopsis and Discussion
A trough is expected to begin to deepen across the western US as strengthening mid-level flow moves southward from the northern Pacific Friday and Saturday. Downstream across the central US, upper-level westerly flow will strengthen across the central/northern Rockies with strengthening lee troughing across the Plains. Persistent southerly flow through the southern and central Plains should establish a broad warm sector across the Plains, bounded to the west by a dryline and to the north by a diffuse warm frontal zone. Scattered thunderstorm development is expected across portions of the central high Plains near a developing surface low and along the warm front, with additional thunderstorms possible along the dryline from eastern Kansas to western Oklahoma. Scattered thunderstorms will also be likely across portions of the lower to mid Missouri Valley.
Central Plains ?
As a short-wave trough moves across the central Plains late Saturday afternoon, scattered thunderstorms are expected to develop near the deepening surface low and the warm front by the afternoon across eastern CO, northwest KS, and western NE. A broad warm sector will be in place across much of the central Plains, with low to mid 60s dew points reaching as far north as southern Nebraska. MLCAPE around 2000-2500 J/kg will be common by the afternoon. Initially, strong deep layer shear and largely linear hodographs will support potential for supercells capable of large to very large hail, damaging winds, and a tornado. As the low-level jet strengthens into the evening, low-level shear will increase but storm mode will also likely shift to become more linear, with broken clusters/bowing segments likely. A few of the mid-range hi-res CAMs depict a stronger bowing segment moving across southern Nebraska into the evening in concert with the increasing of the low-level jet. This may present a more focused corridor of significant wind potential. Confidence at this time in the exact location of this remains low. Higher probabilities may be needed in subsequent outlooks if trends align.
Western Oklahoma/Northwest Texas ?
Much of western Oklahoma and northwest Texas near the dryline will remain capped at the base of the EML. Strong daytime heating and favorable residence time within the dryline circulation may promote an isolated supercell or two with potential for large to very large hail and damaging winds by the late afternoon. Signal for development is most favorable near the Red River in southern Oklahoma where CAM guidance suggests potential and HREF calibrated thunder probabilities are highest.
Midwest/Oh Valleys ?
A leading mid-level shortwave trough with an enhanced belt of 50 kts winds aloft will promote widely scattered thunderstorm development into the mid- to upper Missouri Valley Saturday afternoon. MUCAPE values on the order of 1000-2000 J/kg should support deep convection, and effective bulk shear values near 30 knots within the warm frontal zone may allow for organized convection with an attendant threat for damaging wind.
000 ACUS02 KWNS 150558 SWODY2 SPC AC 150556 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1256 AM CDT Fri May 15 2026 Valid 161200Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL PLAINS... ...SUMMARY... Severe storms capable of large to very large hail, wind damage and perhaps a couple of tornadoes will be possible Saturday afternoon and evening across parts of the central Plains. Scattered thunderstorms will also pose potential for strong to severe winds across the lower to mid- Missouri Valley. ...Synopsis... A trough is expected to begin to deepen across the western US as strengthening mid-level flow moves southward from the northern Pacific Friday and Saturday. Downstream across the central US, upper-level westerly flow will strengthen across the central/northern Rockies with strengthening lee troughing across the Plains. Persistent southerly flow through the southern and central Plains should establish a broad warm sector across the Plains, bounded to the west by a dryline and to the north by a diffuse warm frontal zone. Scattered thunderstorm development is expected across portions of the central high Plains near a developing surface low and along the warm front, with additional thunderstorms possible along the dryline from eastern Kansas to western Oklahoma. Scattered thunderstorms will also be likely across portions of the lower to mid Missouri Valley. ...Central Plains... As a short-wave trough moves across the central Plains late Saturday afternoon, scattered thunderstorms are expected to develop near the deepening surface low and the warm front by the afternoon across eastern CO, northwest KS, and western NE. A broad warm sector will be in place across much of the central Plains, with low to mid 60s dew points reaching as far north as southern Nebraska. MLCAPE around 2000-2500 J/kg will be common by the afternoon. Initially, strong deep layer shear and largely linear hodographs will support potential for supercells capable of large to very large hail, damaging winds, and a tornado. As the low-level jet strengthens into the evening, low-level shear will increase but storm mode will also likely shift to become more linear, with broken clusters/bowing segments likely. A few of the mid-range hi-res CAMs depict a stronger bowing segment moving across southern Nebraska into the evening in concert with the increasing of the low-level jet. This may present a more focused corridor of significant wind potential. Confidence at this time in the exact location of this remains low. Higher probabilities may be needed in subsequent outlooks if trends align. ...Western Oklahoma/northwest Texas... Much of western Oklahoma and northwest Texas near the dryline will remain capped at the base of the EML. Strong daytime heating and favorable residence time within the dryline circulation may promote an isolated supercell or two with potential for large to very large hail and damaging winds by the late afternoon. Signal for development is most favorable near the Red River in southern Oklahoma where CAM guidance suggests potential and HREF calibrated thunder probabilities are highest. ...Midwest/OH Valleys... A leading mid-level shortwave trough with an enhanced belt of 50 kts winds aloft will promote widely scattered thunderstorm development into the mid- to upper Missouri Valley Saturday afternoon. MUCAPE values on the order of 1000-2000 J/kg should support deep convection, and effective bulk shear values near 30 knots within the warm frontal zone may allow for organized convection with an attendant threat for damaging wind. ..Thornton.. 05/15/2026 $$