Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 1257 AM EDT Fri Oct 31 2025 Valid 12Z Fri Oct 31 2025 - 12Z Sun Nov 02 2025 ...Heavy rains over the Pacific Northwest Friday into Saturday... ...Trick or Treating will be dry across much of the Lower 48, except for portions of the Pacific Northwest, northern & central Appalachians, & from the Upper Midwest into the Great Lakes... ...Below average temperatures expected from the Plains into the East; above average temperatures from the High Plains/Rockies to the West coast... An intense cyclone approaching October low pressure records for New England will continue to produce widespread wet weather as it moves through the region Friday. The flood threat from this system remain low as drought conditions have resulted in low stream flows and dry soils. The exception will be over urbanized areas of the Northeast where a period of heavy rain along and ahead of the associated cold front Thursday afternoon into Thursday evening may result in isolated urban runoff issues and where recent leaf fall has clogged drainage. Heavy rains also likely to spread into portions of the Pacific Northwest Friday into early Saturday as an atmospheric river event impacts these areas. At the moment, it does not appear to be a prolonged event, limiting the potential for very heavy totals and keeping any flooding risk at a minimum. From portions of the Ohio Valley through the Cumberland Plateau into the Southeast, rainfall is expected from late Saturday through Sunday into Monday as a weak area of low pressure and a couple fronts help focus precipitation. Much of the country will have good trick or treating weather this evening/tonight. The exceptions will be for areas of the Pacific Northwest, from the Upper Midwest into the Great Lakes, and across the northern and central Appalachians. Temperature wise, a cool weather pattern is on tap from the Plains eastward due to the combination of cool air in the wake of the system pushing through the East and a reinforcing cold air mass moving in behind it, cold enough to induce lake effect precipitation. In contrast, outside the Northwest, areas from the Rockies to the West coast and increasingly across the High Plains will see mostly above average temperatures and dry weather over the next few days. On Monday, a couple record high temperatures are possible along the Colorado Front Range. Roth Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php