Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 350 AM EDT Sat Aug 07 2021 Valid 12Z Sat Aug 07 2021 - 12Z Mon Aug 09 2021 ...Heavy downpours and severe storms expected from the Northern/Central Plains to the Midwest today and Sunday... ...Heavy rainfall and the chance for flash flooding for portions of the Southeast and Pacific Northwest this weekend... ...Hot in the Great Plains, poor air quality due to wildfire smoke continues in the Midwest and Intermountain West... An upper level disturbance is responsible for the development of a frontal system in the northern Plains and Midwest that generates strong-to-severe thunderstorms later today. Severe storms from the TX/OK Panhandles to the Upper Mississippi Valley could produce damaging wind gusts, large hail, and tornadoes. In addition to the severe threat, flash flooding is also a concern this afternoon, especially in northern Wisconsin where a Slight Risk for Excessive Rainfall has been issued. By Sunday, the wave of low pressure inches east across the Midwest, setting up the next round of potentially severe storms from southern Wisconsin on south into eastern Kansas. Portions of the Upper Mississippi Valley may also contend with areas of flash flooding on Sunday. In total, anywhere from 2 to 4 inches of rain in the hardest hit areas of the Midwest is possible this weekend. Two other areas expected to receive measurable rainfall this weekend are the Northwest and Southeast. Starting with the latter, a weakening frontal boundary with a wave of low pressure tracking northeast along it will induce heavy showers and thunderstorms from the southern VA/northern NC Piedmont to the Mid-Atlantic coast. Some storms could be severe and/or cause areas of flash flooding. In fact, a Slight Risk for Excessive Rainfall remains in place in these aforementioned areas as well as a Flash Flood Watch through this evening. The wave of low pressure heads off the coast by Sunday, making for a drier day on Sunday for all but those along the northern Mid-Atlantic coast. In the Northwest, a potent Pacific cold front ushers in wet and cooler conditions this weekend. The cold front reaches the northern Rockies and High Plains by Sunday with a threat for severe storms expected to take shape the second half of the day. Temperature-wise, above normal temperatures will be observed from California and the Southwest to the central Plains and into New England. Parts of the central and southern High Plains could eclipse the century mark while hotter and more humid conditions return to the Northeast. Saturday's coolest temperatures versus normal will be focused in the Southeast and Pacific Northwest. The Southeast begins to warm up on Sunday while the cold front in the Northwest injects below normal temps into the interior Pacific Northwest. The Plains will also heat up with highs ranging from 90-100 degrees up and down the Great Plains. Last but certainly not least, thick wildfire smoke continues to cause poor air quality levels in parts of the Intermountain West and Upper Midwest. Elevated fire weather conditions have been issued for the northern High Plains on Montana today and the northern Great Basin on Sunday. Mullinax Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php