Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 400 AM EDT Sat Jun 30 2018 Valid 12Z Sat Jun 30 2018 - 12Z Mon Jul 02 2018 ...Severe weather and flash flooding possible for parts of the Plains to the Midwest... ...Widespread and dangerous heat wave to continue through the weekend for much of the eastern half of the country... A cold front moving slowly eastward and a surface low lifting through the upper Midwest/Great Lakes on Saturday will remain a focus for potentially strong to severe convection and heavy to excessive rainfall. The Storm Prediction Center has highlighted portions of the eastern Central Plains to the upper Midwest within a slight to enhanced risk for severe weather today, with slight risks also across portions of the central high Plains and the Northeast. The primary threats with these storms will be wind and large hail, but a few tornadoes cannot be ruled out. Given significant moisture pooling along the main boundary, these storms will also be capable of heavy to excessive rainfall and flash flooding, and WPC has placed roughly the same region (from eastern Nebraska to western Wisconsin within a slight to moderate risk on the Day 1 outlook. By Sunday, this system becomes a bit more progressive as the surface low races northward through the upper Great Lakes, which should limit the overall flash flood threat, but severe weather will remain a possibility along the cold front. Refer to the products issued by the Storm Prediction Center and WPC for additional details regarding the severe weather and flash flooding threats. The other big weather story this weekend is the major ongoing heat wave affecting much of the eastern two-thirds of the country this weekend, and extending into the upcoming holiday week. Afternoon high temperatures could be as much as 10 to 20 degrees above normal and combined with high humidity values, will lead to dangerous heat indices approaching or exceeding 100 degrees for many places. Daytime maximum and overnight high-minimum temperature records are in jeopardy and widespread excessive heat warnings/watches and heat advisories are in effect from the central Plains to the Ohio Valley and parts of the Northeast. Elsewhere, hot, dry, and windy conditions will continue Saturday for parts of the Four Corners region, as well as north-central California, leading to an elevated fire weather risk. Red Flag warnings remain in effect for some locations in Utah and California. Across the Southeastern U.S., a weak surface wave will keep showers and thunderstorms in the forecast, with heavy rainfall possible. Santorelli Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php