Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 353 PM EDT Sat Jul 13 2024 Valid 00Z Sun Jul 14 2024 - 00Z Tue Jul 16 2024 ...Threat for extremely dangerous heat shifts from the West to much of the central/eastern U.S.... ...Multiple rounds of storms to bring the threat of large hail, damaging winds, and isolated flash flooding from the Northern Plains to the Great Lakes... ...Monsoon showers expected for the Four Corners region with locally heavy rainfall and isolated flash flooding possible... The heat wave that has plagued the West for over a week will remain in place through Saturday as a stubborn upper-level high sits overhead. Forecast temperatures across the Great Basin and interior California this afternoon are into the low to mid-100s, with 110s in the Desert Southwest. A few more near-record tying/breaking highs may be reached. The ridge will begin to shift a bit east on Sunday, providing a little relief for many areas as highs drop a few degrees closer to more typical Summer averages. Pockets of excessive heat with highs into the 100s will remain over portions of the northern Great Basin. Unfortunately, attention then turns to the central and eastern U.S. as heat begins to expand across the region. Forecast highs into the mid-90s for the Mid-Atlantic and Midwest, upper 90s to low 100s for the Southeast, and low to mid-100s over portions of the central Plains will pose a threat for higher levels of heat stress for those without effective cooling and hydration. The heat will only get more intense Wednesday as the Mid-Atlantic soars into the upper 90s to low 100s and the heat spreads northward into New England with low to mid-90s expected. Numerous near record-tying/breaking high temperatures are possible over the central High Plains and Southeast Sunday, and along much of the East Coast by Monday. The intensity of the heat in urban areas in the Southeast and along the East Coast as well as the expected duration (into at least midweek) will become increasingly dangerous and potentially deadly. Embedded shortwaves in strong westerly flow over a frontal boundary in the Upper Mississippi Valley and Northern Plains will help to trigger rounds of thunderstorms across the region the next couple of days. Sufficient moisture, moderate instability, and deep-layer shear given the strong flow aloft will bring the chance of severe weather with these thunderstorms. A similar scenario will play out through today (Saturday), Sunday, and Monday, with the threat of large hail and damaging winds with initial supercell development in the afternoon and early evening, transitioning to primarily a damaging wind threat later in the evening and overnight as storms tend to grow upscale into one or more convective systems. The Storm Prediction Center has outlined portions of the northern High Plains with an Enhanced Risk of severe weather (level 3/5) through late Saturday given a higher threat for significant hail, with a Slight Risk (level 2/5) east through the Northern Plains into the Upper Midwest. A Slight Risk is again in place Sunday for the northern Plains, with a Slight Risk over portions of the Upper Mississippi Valley into the Great Lakes on Monday. In addition to severe weather, locally heavy rainfall will also be possible, with the multiple rounds of storms traversing the Northern Plains into the Great Lakes region posing an isolated threat for flash flooding, especially as antecedent conditions become wetter with each round. A Monsoonal pattern will remain in place over the Four Corners region, with the upper-high overhead helping to funnel in higher moisture into the region. Daily scattered thunderstorms producing some heavier downpours will pose an isolated risk for flash flooding, particularly over any burn scars. Elsewhere, some showers and storms can be expected along the immediate East Coast Sunday as a quasi-stationary boundary lingers through the region. Some additional storms will be possible over the Northeast Monday as an upper-level wave passes overhead. Daily thunderstorms are also expected over Florida and westward along the coast Sunday, with the chances becoming more isolated on Monday. Putnam Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php