Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 445 AM EDT Sat Aug 15 2020 Valid 12Z Sat Aug 15 2020 - 12Z Mon Aug 17 2020 ...Developing low pressure system will likely bring another round of flooding rains across parts of the central/southern Appalachians to the Mid-Atlantic today into Sunday morning... ...Threat of flash flooding and severe weather gradually diminish today across the upper Midwest... ...Record heat will gradually moderate over the southern Plains but will expand and intensify across the interior western U.S.... A fairly strong and compact low pressure system responsible for the latest rounds of severe weather and heavy rainfall across the upper Midwest is moving into central Canada. As the low moves further away, the threat of severe weather will decrease ahead of a trailing cold front which is moving steadily into the Great Lakes today. Nevertheless, some locally heavy rain associated with thunderstorms will still be possible. Meanwhile, a weak low pressure center forecast to form near the tail end of the front will raise the threat of strong thunderstorms and heavy downpours over the central High Plains later today into tonight. Cool air ushering in behind the cold front will drop temperatures appreciably into the 50s and 60s across the northern and central Plains for the next couple of mornings. In the mean time, a slowly developing low pressure system forming along a slow-moving front will interact with very moist air in the eastern U.S. to bring another round of flooding rains across parts of the central/southern Appalachians to the Mid-Atlantic today into Sunday morning. The highest chance of heavy rainfall should be across the interior Mid-Atlantic tonight into Sunday morning as the low pressure center passes to the south. Any downpours will surely raise the possibility of flash flooding in these areas where the ground is already saturated from recent heavy rainfall. The low pressure system is forecast to edge slowly eastward and move off the coast Sunday night, ending the heavy rain across the Mid-Atlantic. However, a weakening front approaching from the west could touch off some showers and thunderstorms early on Monday along the interior sections of the East Coast. In contrast to the wet weather in the East, hot and mainly dry conditions are expected for the western U.S. and the southern Plains underneath a strengthening upper-level ridge of high pressure. Excessive Heat Watches/Warnings and Heat Advisories are in effect for much of the western U.S. While temperatures in Texas will gradually moderate closer to normal during the next couple of days, the heat will expand and intensify across the interior Pacific Northwest into the Great Basin where widespread record high temperatures will be likely for the coming days. Actual high temperatures are forecast to top 100 degrees at many locations, along with a heightened risk of wildfires. Kong Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php