Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 200 AM EDT Mon Aug 25 2025 Valid 12Z Mon Aug 25 2025 - 12Z Wed Aug 27 2025 ...Excessive rainfall is a threat across portions of the Southwest through Tuesday... ...Flash flooding a concern across portions of Colorado, Kansas, Oklahoma, and Arkansas through Wednesday... ...The Pacific Northwest will remain hot Monday and Tuesday; cool conditions spread through the East... Through Wednesday, monsoonal moisture, diurnal heating, and upper-level impulses will produce showers and thunderstorms over portions of the West. Slight Risks of excessive rainfall/flash flooding exist across portions of the Southwest Monday and Tuesday and Idaho/southwest Montana on Wednesday. Elevated convection with heavy rainfall north of a front will develop at times over parts of Colorado, Oklahoma, Kansas, and Arkansas through Wednesday; a Slight Risk of excessive rainfall is depicted over portions of these areas. For the West, the main concern is flooding of dry washes/arroyos, urban areas, burn scars, and box canyons. For areas east of the Rockies, hourly amounts to 2.5" would be problematic in urban areas. Swaths of heavy rain each day are expected to increase soil saturation over time, making areas increasingly sensitive to further heavy rainfall. Meanwhile, warm core ridging across the Northwest will aid and abet a heat wave across Northwest continuing on Monday and Tuesday, before losing its grip on the region on Wednesday. Record highs are expected to be threatening in more locations across Washington and Oregon on Monday than Tuesday; temperatures will rise to near 100F. This heat will be dangerous, posing a threat to anyone without effective cooling and adequate hydration. Numerous daily high temperature records are likely to be broken. For many areas, there will be little nighttime relief from the extreme heat, with overnight lows remaining well above normal. Extreme heat is dangerous even at night when temperatures do not cool down. Stay informed and take steps to protect yourself from heat-related illnesses. For information on staying cool and safe, visit www.weather.gov/safety/heat. As temperatures rise, limit outdoor activity, stay hydrated, and ensure access to air-conditioning and other cooling areas. Meanwhile, east of the Rockies and north of the Gulf Coast, large swaths of below average temperatures are expected, with temperatures more reminiscent of early fall than late summer under the aegis of strong high pressure (by August standards). Cool to cold conditions are expected overnight from the Gulf Coast northward, with resplendent sunshine during the day over portions of the Midwest, Appalachians, and much of the East. Record lows will be threatened on Tuesday at International Falls, Minnesota (close to freezing) and well as portions of the Midwest where 40s and 50s are forecast. On Wednesday, the record low territory expands across the Midwest, towards the southern Great Lakes and into the Southeast, encompassing a broader area of 40s and 50s. In areas with rain, such as Kansas/Oklahoma on Monday, the ArkLaTex and Red River Valley of the South on Tuesday, and Kansas on Wednesday, highs may only reach into the 60s and 70s threatening record cold maxima for the dates. Lake Effect and Lake enhanced showers and thunderstorms are expected Monday through Wednesday, with convective coverage near the Great Lakes decreasing noticeably late on Tuesday and during the day Wednesday. Roth Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php