Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 358 PM EDT Sat Jul 23 2016 Valid 00Z Sun Jul 24 2016 - 00Z Tue Jul 26 2016 ...Dangerously hot temperatures expected across portions of the central and eastern U.S. this weekend... ...Severe thunderstorms possible across portions of the Northern Plains and Upper Midwest tonight... ...Heavy rainfall and flash flooding possible from the Northern Plains to the Ohio Valley... The big story across the nation this weekend will be an expansive area of high pressure at the mid and upper levels of the atmosphere anchored over the Southern Tier states over the next several days. This will result in afternoon high temperatures across portions of the central and eastern U.S. as much as 5 to 15 degrees above normal, which may threaten the record books in many places. There is a widespread area of heat advisories and excessive heat warnings in place from the Central Plains/Midwest to the Ohio Valley/Mid-Atlantic for heat indices approaching and surpassing 100 degrees. Widespread showers and thunderstorms are expected to continue across much of the Upper Midwest and Upper Great Lakes tonight ahead of a cold front pushing eastward through the Northern Plains this afternoon. Storms will be capable of producing severe weather and flash flooding. Wet weather will push into the Ohio Valley and Northeast Sunday and Monday, with localized heavy rainfall and flash flooding possible from the Middle Mississippi Valley to the Ohio Valley. Behind the boundary, temperatures should return to near normal and more comfortable values. Elsewhere, afternoon showers and thunderstorms are possible across portions of the Southeast and Gulf Coast states as a warm, moist, and unstable air mass remains in place. For the Southwest and Rockies, weak monsoonal flow into the region keeps mainly diurnally driven showers and storms in the forecast the next couple of days. Santorelli Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php