536 FXUS01 KWBC 190624 PMDSPD Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 214 AM EDT Sat Sep 19 2026 Valid 12Z Sat Sep 19 2026 - 12Z Mon Sep 21 2026 ...Heavy Rainfall threat across portions of the Midwest, Ohio Valley, Great Lakes, Central Plains into Northern Rockies through Saturday... ...Heavy Rainfall threat expands into portions of the Mid-Atlantic and Northeast on Sunday... ...Severe weather threat across portions of the central/southern Plains and Rockies, Ohio Valley, and Southeast through the weekend... A progressive northern stream trough will move eastward from the northern Plains into the Great Lakes toward the Northeast through the weekend bringing chances for showers and thunderstorms across the Upper Midwest into the Great Lakes, Ohio Valley, and eventually the Northeast. The trough will push the surface frontal boundary eastward and will drape across the Midwest into the central/northern Plains and Rockies. The boundary will provide sufficient forcing, while interacting with deep moisture and instability, which will support periods of moderate to heavy rain with locally excessive totals. The heaviest rainfall/flash flooding concerns will be over portions of the Midwest, Great Lakes, and Ohio Valley for Saturday, where the system is expected to produce multiple rounds convection. Meanwhile, further west, scattered thunderstorms may produce localized flash flooding over the central/northern Plains into the Rockies through the weekend, with a concentrated area for heavier rainfall rates over portions of Montana for Saturday. On Sunday, showers and thunderstorms will continue to slowly push further east-northeast into the Ohio Valley and Mid-Atlantic and portions of the Northeast. Continuous interaction with warm moisture will reinforce excessive rainfall concerns over portions of the Midwest and Ohio Valley/Great Lakes, while expanding the risk into portions of the Northeast and Mid-Atlantic, where soil remains saturated from previous rainfall. By late Sunday into early Monday, the focus for heavier rainfall continues to shift toward the coastal areas over the Northeast and Mid-Atlantic. Additionally, Storm Prediction Center (SPC) has highlighted a risk for severe thunderstorms capable of producing hail and severe winds across portions of the central and southern Plains/Rockies, Midwest, Ohio Valley, and Southeast through the weekend. Across the Southeast, warm Gulf moisture will support scattered to numerous showers and thunderstorms through the weekend. Slow moving storms may produce high rainfall rates, which may lead to isolated flash flooding over portions of the south Florida. Additionally, residual anomalous moisture may lead to thunderstorms over portions of Texas and southern Plains, which pose a risk for localized heavy rainfall through the weekend. Otherwise, above average temperatures will remain concentrated across the southern Plains, mid to lower Mississippi Valley, and the Southeast where persistent ridging will support highs in the 90s to lower 100s and warm overnight temperatures. Some locations may approach or exceed daily records and Heat Advisories remain in affect. Elsewhere, temperatures will trend closer to or below normal behind the frontal boundary. Oudit Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php $$