Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 403 AM EDT Sat Aug 06 2022 Valid 12Z Sat Aug 06 2022 - 12Z Mon Aug 08 2022 ...Monsoonal rainfall in the Western region ahead of an advancing frontal boundary, with the threat shifting southeastward today... ...Much needed relief from the heat and humidity in the Northern Plains this weekend behind an advancing cold front... ...Unsettled weather will continue in the Northeast as a slow-moving frontal boundary triggers showers and thunderstorms... A sprawling, slow-moving cold front will be draped from the Intermountain West, across the Plains/Midwest to the Great Lakes/Northeast over the next few days. Cooler air will filter into the Pacific Northwest and spread inland to the Intermountain West. The daily maximum temperatures will be about 5 to 15 degrees F cooler than seasonal average this weekend. In contrast, the Northeast will have hot, humid and unsettled weather will persist across into early next week as the cold front weakens upon approaching the region. Across the Plains, temperatures are expected to soar into the upper 90s to low 100s across the central Plains and Midwest. A large portion of the central U.S., western Washington/Oregon, southeast Michigan and the Northeast have Heat Advisories and Excessive Heat Warnings in effect. The frontal boundary will also be the focus for showers and thunderstorms from portions of the Great Basin, Northern High Plains, Upper Mississippi Valley, Great Lakes region to the Northeast. Some of these storms may become strong or severe today across the Upper Mississippi Valley. Periods of heavy rainfall may increase the threat for rapid runoff and localized flash flooding, especially over areas that have excessive rainfall and widespread flooding. WPC has a Slight Risk for excessive rainfall in place over parts of the eastern Tennessee Valley/Central Appalachians. Monsoonal transporting northward south of this boundary will continue to fire off convection across parts of the Southwest and Southern Rockies. The isolated areas of heavy rain may lead to flash flooding. There is also a Slight Risk for excessive rainfall across parts of the Great Basin. As the area of precipitation shifts, area of elevated risk shifts to Arizona, northern New Mexico/southern Colorado for the start of the week. Campbell Graphics are available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php