SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0241 PM CDT Wed Apr 16 2025 Valid 162000Z - 171200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS LATE THIS AFTERNOON INTO TONIGHT FROM THE TEXAS PANHANDLE TO NORTHEAST KANSAS AND VICINITY... ...SUMMARY... Isolated large hail and strong-severe outflow gusts are possible this evening into tonight from parts of the southern and central Plains into the lower to mid Missouri Valley. ...Discussion... The forecast is on track, and no change is needed to the previous outlook. ..Smith.. 04/16/2025 .PREV DISCUSSION... /ISSUED 1116 AM CDT Wed Apr 16 2025/ ...TX Panhandle to northeast KS and vicinity through tonight... Upper ridging that currently extends from the southern Plains into eastern Manitoba/northwest Ontario is forecast to shift eastward throughout the period. This eastward shift will occur as a shortwave trough drops south-southeastward through the Pacific Northwest/northern Rockies, phasing with the upper low off the southern/central CA Coast as it does. This evolution will result in strengthening southwesterly flow aloft from the Southwest into the central Plains, which in turn will foster a deepening lee surface trough across the High Plains and eventual surface cyclogenesis over the central High Plains. Moisture return will also increase across the southern Plains, with upper 50s/low 60s dewpoints likely across much of OK by this evening. Some thunderstorm development could occur during the late afternoon/early evening where the western edge of this moisture interacts with a dryline that extends south from the developing central High Plains surface low. Convergence along this boundary will be modest and convective initiation remains uncertain given the warm mid-level temperatures and resultant capping. Even so, an isolated storm or two appears possible from southwest KS into the eastern TX Panhandle. Strong mid-level flow (and resulting long hodographs) support a supercellular storm mode with any convection that is also to deepen and persist. Large hail and damaging gusts would be possible with any supercells. Higher thunderstorm coverage is anticipated later tonight as the surface low and any afternoon storms move eastward across southwest/south-central KS into the greater low-level moisture, and a strengthening low-level jet fosters increased warm-air advection. Hail will likely be the primary risk with these storms, but the dry subcloud layer in place could still support a few gusts to the surface as well. Overall severe coverage is still expected to remain low enough to keep 5%/Marginal probabilities.