A frontal system and associated low pressure are driving widespread rain across the Upper Midwest and Northeast on September 26, 2026, with National Weather Service forecasts showing 80-100% probability of measurable precipitation and accumulations of 0.5-1 inch in places like New York and parts of the Great Lakes region. In contrast, high pressure maintains mostly sunny conditions and only 30% or lower shower chances in Miami and much of the Southeast, consistent with late-September climatology. Model consensus from NWS guidance highlights northwesterly flow and coastal moisture as key intensifiers for northern areas, while southern steering patterns limit convective activity. Updated NWS tabular forecasts and radar observations through the evening will refine exact thresholds for market resolution based on official daily totals from The Weather Company.