Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 351 PM EDT Sun Aug 01 2021 Valid 00Z Mon Aug 02 2021 - 00Z Wed Aug 04 2021 ...A cooler than normal temperature regime is expected to engulf much of the eastern half of the Lower 48 the first half of the week, while temperatures gradually heat up along the West Coast... ...Daily rounds of showers and thunderstorms to become a common occurrence across the Deep South and Southeast this week... ...More rounds of monsoonal moisture expected across the interior western U.S. with flash flooding possible from the Great Basin to the Rockies... The first few days of August start off on a generally cooler than normal note thanks in large part to a deep upper level trough setting up shop over the eastern third of the CONUS. A cold front gradually pushing its way through the South is ushering in cooler temperatures, but it is also responsible for triggering scattered showers and thunderstorms this afternoon. Some thunderstorms may be severe, most notably in the Carolinas where a Severe Thunderstorm Watch is in effect this afternoon. Ahead of the front, one more day of sultry conditions is on tap along the Gulf Coast Sunday before the front arrives on Monday. The front will have widespread showers and thunderstorms accompanying it, which will in turn help to drop temperatures to more seasonal levels. By Tuesday, the front becomes quasi-stationary and a wave of low pressure looks to form near the Carolina coastline, causing easterly flow to develop and force temperatures to remain at below normal levels in the Southeast. This front becomes the focus for daily episodes of showers and thunderstorms that is forecast to produce heavy rainfall totals later in the week. Farther north, a reinforcing cold front is sparking showers and thunderstorms across the interior Northeast this afternoon. These storms will track east across the region this evening with damaging winds, hail, and flash flooding possible within the more intense storms. In wake of this frontal passage, a cool and dry air mass across the northern Plains will be ushered into the Great Lakes and the Northeast begin the new work week. Over the Mid-Atlantic region however, the front is forecast to stall late Monday into Tuesday, which will encourage showers and thunderstorms to stick around along the coast. More showers and thunderstorms are expected all the way down into Florida and along the Gulf Coast where the front is forecast to stall out. In the Pacific Northwest, an influx of monsoonal moisture from the south should help cool down the temperatures today across the interior sections, breaking the recent spell of excessive heat. However, there is no shortage of monsoonal moisture across the Intermountain West. The associated rainfall is a welcome sight to the drought-stricken West, but downpours associated with some thunderstorms are capable of producing heavy rainfall rates that could trigger areas of flash flooding. Locations most at risk for flash flooding are where antecedent soil conditions are overly saturated or near burn scars. The Excessive Rainfall threat in Idaho and the southern High Plains this afternoon becomes more focused along the spine of the Rockies on Monday. By Tuesday, the Excessive Rainfall threat diminishes in the Northwest, but a Slight Risk remains in place in the portions of Colorado and New Mexico. In addition, hotter conditions return up and down the West Coast on Tuesday. Air Quality Alerts remain in effect for portions of the interior Northwest, Arizona, Colorado, Wyoming, and the upper Midwest due to smoke associated with wildfires over western North America being transported into these areas. Mullinax Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php