Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 406 AM EDT Thu Aug 20 2020 Valid 12Z Thu Aug 20 2020 - 12Z Sat Aug 22 2020 ...Slow moderation with the record heat continues in the western U.S. but fire danger remains a threat... ...Scattered showers and thunderstorms will persist for the coming days across the southeastern quadrant of the country... An upper-level high located over the Southwest has weakened slightly, allowing the record heat to become less intense across much of the western U.S. Slight cooler air filtering into the northwestern U.S. behind a Pacific cold front will also keep temperatures from reaching record levels for the next couple of days. On the other hand, dry thunderstorms triggered ahead of the cold front will raise the threat wildfire across the Great Basin and northern Rockies today, before ease off somewhat on Friday. In addition, some areas of California and Colorado have Air Quality Alerts in place due to smoke from ongoing fires. Some monsoonal showers and thunderstorms are expected across the Rockies into the southern Great Basin today but these storms are forecast to be more suppressed on Friday as the upper high begins to re-strengthen. Some of these storms will also spread into the High Plains. In contrast, much of the eastern half of the country will experience cooler than normal temperatures due to persistent upper-level troughing. A stalled front interacting with tropical moisture will keep a good chance of showers and thunderstorms for much of the Southeast including Florida as well as the Mid-Atlantic for the coming days. Rainfall totals in most areas should not be significant, but locally heavy rainfall could cause isolated concerns for flooding or flash flooding. A few strong storms containing gusty winds cannot be ruled out either. As the Bermuda High is forecast to strengthen and extend westward, these showers and storms will begin to edge slowly northward farther into the Mid-Atlantic and the central Appalachians by this weekend. Kong Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php