Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 350 AM EDT Sat Jul 19 2025 Valid 12Z Sat Jul 19 2025 - 12Z Mon Jul 21 2025 ...Expansive Excessive Rainfall threat to encompass much of the Midwest, Ohio Valley, and Mid-Atlantic with locally significant areas of flash flooding possible... ...Severe weather likely over parts of the Northern/Central Plains, Midwest, Mid-Atlantic, and Northeast this weekend... ...Dangerous summer heat wave to grow across the Central Plains, Mississippi Valley, and Southeast into next week... This weekend's weather pattern has a "Ring of Fire" look over the eastern two-thirds of the Lower 48. A ridge of high pressure atop the southeastern U.S. will keep the South mired in sultry conditions while an active jet stream is situated over the northern periphery of the Southeast ridge. Over the Southern Plains, a steadfast low-level jet will direct rich tropical moisture northward towards a semi-stationary frontal boundary oriented west-to-east from the Midwest to the Ohio Valley and Mid-Atlantic. As Pacific disturbances embedded within the west-to-east oriented jet stream race across the northern U.S., they will help to enhance the strong-to-severe thunderstorms along and north of the elongated frontal boundary. These storms will tap into the tropical air-mass and pose a broad flash flood threat across a large section of the east-central U.S.. WPC has a Slight Risk (threat level 2/4) in place from eastern Nebraska all the way to the Mid-Atlantic coast today. The front does not make much progress east on Sunday, keeping much of Corn Belt and Ohio Valley under a Slight Risk for Excessive Rainfall once again. There is the potential for training thunderstorms that could result in locally significant flash flooding in parts of the Midwest and Ohio Valley this weekend. Flash flooding is not the only threat that portions of the Great Plains, Midwest, and Mid-Atlantic face this weekend, as the same storms that pose a flash flood threat could be severe in some cases. The Storm Prediction Center (SPC) has issued three separate Slight Risks (threat level 2/5) for portions of these regions. By Sunday, severe storms are still possible from the Great Plains to the Northeast, but a strong cold front passing through the Northeast will become a focus for organized severe storms. SPC has a Slight Risk from the Poconos on east to the Maine coast with metro areas such as NYC, Hartford, Providence, and Boston within the Slight Risk area. Severe storms this weekend will be capable of producing damaging wind gusts and large hail, with the potential for tornadoes as well. Look for additional thunderstorms capable of producing flash floods and severe weather to stick around in parts of the Northern Plains and Southeast to kick-off the start of the upcoming work-week. The aforementioned ridge of high pressure over the Southeast will lock in place the kind of searing heat and oppressive humidity that occurs during the "Dog Days of Summer" from the Southern Plains and Lower Mississippi Valley to the Southeast. HeatRisk shows a growing footprint of Major Impacts from the Ozarks and Ohio-Mississippi River Confluence to the Southeast Coast. There are some localized cases of Extreme Impacts in parts of southern Georgia and northern Florida. Heat Indices throughout these regions will range between 105-110F with some instances where heat indices reach 115F. Extreme Heat Warnings and Watches are out for portions of the Central Plains and Middle Mississippi Valley that linger into the first half of the upcoming work-week. There are also Heat Advisories for parts of Oklahoma, Arkansas, and along the Southeast coast. The Southeast ridge looks to become a more pronounced heat dome over the east-central U.S. later next week. Please review our ongoing Key Messages for additional details on next week's expanding heat wave. Mullinax Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php