SPC AC 200503 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1203 AM CDT Sun Sep 20 2020 Valid 201200Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Scattered general thunderstorm activity is expected over parts of the Upper Mississippi Valley and central Plains. Elsewhere, any severe threat associated with Tropical Storm Beta is forecast to remain offshore through Monday morning. ...Northern Plains... A negative-tilt upper trough will move across the northern High Plains and Dakotas during the day, reaching western Ontario by Monday morning. At the surface, a surface low will develop into Manitoba, while a dryline pushes into the eastern Dakotas during the afternoon. Dewpoints in the lower 50s F will be common, contributing to a few hundred J/kg MUCAPE. Overall ascent with this system appears to be limited, with only weak pressure falls throughout the day as the low develops to the north. In addition, forecast soundings show capping east of the dryline, and elevated storm potential into Minnesota. The end result should be limited storm coverage, with little severe threat. ...Upper Texas Coast... Tropical Storm Beta is forecast to slowly approach the middle to upper Texas Coast, with the center remaining offshore through the Day 1 period ending 12Z Monday. In advance of this system, rather dry low-level trajectories will persist, with a strong northerly component to the surface winds across coastal Texas. Although low-level moistening will gradually occur into Monday morning, forecast soundings from various models still indicate that the bulk of the surface-based instability will remain offshore. As such, tornado probabilities are forecast to be less than 2% over land. If the system ends up moving faster than expected, low tornado probabilities may be required just before 12Z Monday along the Middle/Upper Texas Coast. ..Jewell/Wendt.. 09/20/2020 NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1300Z