SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0753 PM CDT Sat Aug 12 2023 Valid 130100Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF SOUTH DAKOTA AND NORTHERN NEBRASKA...AND FROM SOUTHEASTERN OHIO AND NORTHERN WEST VIRGINIA TO SOUTHWESTERN NEW ENGLAND... ...SUMMARY... Severe-weather risk will continue this evening across parts of the upper Ohio Valley and Northeast, as well as parts of South Dakota and Nebraska, and over portions of the Kansas and Oklahoma vicinity. ...Eastern Ohio/Pennsylvania/northern West Virginia to New York/northern New Jersey/western Connecticut... Scattered to widespread thunderstorms are ongoing across New York, Pennsylvania, and portions of surrounding states ahead of an advancing/segmented cold front crossing the lower Great Lakes/Ohio Valley. With an amply unstable airmass remaining across much of the area, storms are expected to continue this evening, before diminishing into the overnight hours. In the meantime, with enhanced deep-layer westerly/west-southwesterly flow, in the 40 to 60 kt range at mid levels, shear will continue to support organized/locally severe storms over the next few hours, with damaging winds the primary severe risk. ...Parts of South Dakota and northern Nebraska... Ahead of a short-wave trough digging southeastward out of western Canada toward the northern High Plains, thunderstorms are ongoing across southern and western South Dakota. The convection is occurring in a zone of moderate instability, and as a south-southwesterly low-level jet continues to strengthen. With 35 to 45 kt mid-level west-southwesterly flow atop the low-level southwesterlies, shear will continue to support locally intense updrafts this evening, along with attendant risk for large hail and locally damaging wind gusts as storms gradually spread southeastward toward northern Nebraska. ...Southern Kansas south to the Texas Panhandle and Oklahoma, and eastward toward the Ozarks... A developing southerly low-level jet across the southern Plains will maintain fairly widespread convection this evening and into the overnight period -- particularly across the Kansas/Oklahoma areas. With an amply unstable airmass in place away from areas where substantial precipitation has already occurred, and given favorably strong/veering flow with height, isolated instances of hail/wind will remain possible with the strongest updrafts. ..Goss.. 08/13/2023
