SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1215 PM CDT Sun Jun 22 2025 Valid 231200Z - 241200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE CENTRAL PLAINS NORTHEASTWARD TOWARD THE UPPER GREAT LAKES... ...SUMMARY... Strong to potentially severe storms are possible Monday from parts of the Great Lakes into the central Plains. ...Synopsis... A prominent upper high will be centered over the Appalachians, providing hot conditions over much of the eastern CONUS. Early in the day, a shortwave trough will exit the far northern Plains, ejecting across Ontario. Meanwhile, a shortwave trough will move from parts of CA into the Great Basin, within a broader upper trough. At the surface, High pressure will exist over much of the East beneath the upper ridge, though weak troughing will occur during the day over the Mid Atlantic. Another area of high pressure behind the northern Plains wave will push east into the upper MS Valley, with a cold front roughly from central WI into western KS by 00Z. A very moist air mass will exist east of this cold front, and, over much of the East. Strong to severe storms are most likely along the Plains front, although scattered storms will also be likely over the TN Valley and Mid South, though with less severe potential. Finally, isolated storms may occur over parts of the Appalachians beneath the upper High. ...Central Plains into the upper Great Lakes... Strong heating will occur ahead of the cold front, where dewpoints will range from the upper 60s F to lower 70s F. This region will also be within a plume of midlevel moisture spreading northward west of the upper ridge. As such, the high PW air mass along with surface convergence near the front should easily support afternoon storms, most likely from WI southwestward to perhaps the OK/TX Panhandles by 00Z. Deep-layer shear and mean winds in general will not be very strong along the frontal zone, but perhaps a bit stronger over northern areas as the upper wave glances the area. The end result should be an elongated area of afternoon storms. Some of these storms may briefly contain marginal hail due to moderate instability and modest midlevel lapse rates, but storms will likely merge quickly over most of the area with strong to locally damaging gusts. ..Jewell.. 06/22/2025