Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 400 AM EDT Sat Jun 15 2024 Valid 12Z Sat Jun 15 2024 - 12Z Mon Jun 17 2024 ...Multiple rounds of severe thunderstorms and locally heavy rain expected to impact various locations in the northern and central U.S. through the next couple of days... ...Late-season wet snow is forecast for the northern Rockies beginning on Monday... ...A plume of tropical moisture is forecast to reach the central Gulf Coast on Monday... ...A heat wave will quickly spread from the northern Plains this weekend into the Great Lakes on Monday... As a series of fronts pushes the showers and storms off the East Coast early this morning, an active and changeable weather pattern will establish across the Pacific Northwest. The unseasonably cold and blustery conditions across this region will be in stark contrast with the heat that is forecast to quickly spread from the northern Plains this weekend, reaching into the Great Lakes on Monday. Areas in between these temperature extremes will be under an active storm track where low pressure systems will develop and move through in quick succession. The first round of showers and storms associated with a leading system is forecast to spark thunderstorm activity from the central Plains early this morning to the upper Midwest by tonight. Multiple rounds of heavy rain associated with these storms could lead to areas of flash flooding between eastern Nebraska and northern Wisconsin. Additionally, a trailing and stronger low pressure system is forecast to intensify and move quickly across the northern Plains tonight. This system will help produce strong to severe thunderstorms across parts of eastern Montana into North and South Dakota. Unseasonably cold and windy weather will continue into Sunday and Monday across the Northwest as yet another cold upper trough reaches the Pacific Northwest. This system will reinforce the unseasonably cold and windy conditions across the region on Monday along with wet snow moving into the northern Rockies, therefore prompting the issuance of Winter Storm Watches. Meanwhile, an area of rain and thunderstorms is expected to develop and expand across the northern Plains toward the upper Midwest where a stationary front strengthens ahead of a developing low pressure system over the central High Plains. Across the Florida Peninsula, the threat of heavy rain continues to diminish as the main tropical moisture plume is forecast to swing farther west and head toward the central Gulf Coast during the next couple of days. Nevertheless, some thunderstorms that manage to develop over southern Florida could result in local flooding issues given the already saturated soil. By Monday morning, heavy rain associated with the tropical moisture plume could begin impacting the central Gulf Coast region. In contrast, a refreshingly dry airmass behind a cold front should lead to beautiful weather this Father's Day weekend throughout the Northeast, Mid-Atlantic, and Ohio Valley. The other main weather story this weekend will be the simmering heat impacting areas from the Southwest to the Gulf Coast and Southeast. Highs are forecast to reach the triple digits throughout much of the Desert Southwest, with upper 90s stretching from the Southeast to parts of the Southern Plains. Above average temperatures are also forecast across the central Great Basin and northern Plains ahead of a cold front, with well below average temperatures encompassing the Pacific Northwest. By Sunday, an upper level ridge is anticipated to begin building across the Eastern U.S., with anomalous heat starting in much of the Midwest, Central Plains, and Tennessee Valley. Highs are forecast to reach the upper 90s, with maximum heat indices near 105 degrees. When combined with warm overnight lows, major heat risk could affect anyone without effective cooling and/or adequate hydration. Be sure to remain weather aware and follow proper heat safety! Kong/Snell Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php