Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0347 AM CDT Thu Oct 02 2025 Valid 051200Z - 101200Z ...DISCUSSION... Medium-range guidance indicates that blocking within the westerlies across the mid-latitude eastern Pacific will remain prominent into the middle to latter portion of next week. However, one mid-level high forming off the Pacific coast this weekend may be relatively short-lived, and subsequent developments off the Pacific into North America remain unclear, based on rather large spread apparent in the model output. Early in the period, a still notable, but perhaps weakening, mid-level short wave perturbation, and associated compact surface cyclone, may quickly migrate from the eastern Dakotas through northwestern Ontario during the day Sunday. In the presence of seasonably strong and sheared lower/mid-tropospheric wind fields, there appears at least some potential for renewed strong to severe thunderstorm development, mainly across parts of north central Minnesota through the western Lake Superior vicinity by Sunday evening. However, mostly due to a continuing lack of better low-level moisture return, potential for destabilization supportive of more than a relatively isolated/marginal severe risk still seems low or at least uncertain. Elsewhere, there appears at least some signal for increasing convective potential ahead of an amplifying short wave trough and associated cold front advancing southeast of the lower Great Lakes region, which could impact the Northeastern urban corridor by late Wednesday. At this point, this appears most notable in ECMWF/ECENS related output, compared to other model output, at a period of increasing model spread and low predictability.
