SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1145 PM CDT Sat Sep 27 2025 Valid 291200Z - 301200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for severe thunderstorms appears negligible Monday through Monday night. ...Discussion... Latest model output indicates little change from prior runs concerning the larger-scale flow evolution through this period. Amplification within the westerlies is forecast to translate eastward, with mid-level ridging building across much of interior Canada and adjacent portions of the northern U.S. and downstream troughing slowly digging across the northwestern Atlantic through Canadian Maritimes and northern New England. Upstream, large-scale troughing across the mid-latitude eastern Pacific into western North America may lose some amplitude, as a couple of embedded short waves progress northeastward inland of coastal areas. However, it appears that deeper troughing will be reinforced offshore of the southern British Columbia/Pacific Northwest coast by a couple of much more vigorous digging short wave perturbations, which models indicate will probably provide support for renewed strong cyclogenesis across the northeastern Pacific. In the southern mid- to subtropical latitudes preceding this regime, mid-level troughing within generally weak flow is forecast to slowly shift northeast and east of the southern Rockies into the Great Plains Monday through Monday night. However, a modest blocking downstream high will probably be maintained across the Midwest, with weak mid-level troughing lingering across the Southeast. A pair of tropical cyclones are likely to continue slowly migrating north-northwestward across parts of the subtropical western Atlantic, including one north of the Bahamas toward the Carolina coast. ...Southeast Atlantic coastal areas... Based on latest model output concerning the most probable track of Tropical Depression Nine through 12Z Tuesday, the environment becoming potentially conducive to low-topped supercells capable of producing tornadoes, as it perhaps strengthens to a hurricane to the east of the Florida Peninsula, will likely remain well offshore of south Atlantic coastal areas. ..Kerr.. 09/28/2025
