Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 348 AM EDT Thu Sep 19 2024 Valid 12Z Thu Sep 19 2024 - 12Z Sat Sep 21 2024 ...Severe thunderstorms possible in the eastern Plains and Upper Midwest today... ...Late-summer heat forecast from the southern/central Plains to the Upper Midwest... The main weather story for the next couple of days will be a strong occluded low and frontal system bringing impactful weather to the Plains and Midwest. The central low will gradually lift north into southern Canada today while it pushes a strong cold front across the eastern Plains and Upper Midwest. Precipitation will taper off in Montana and the northern Plains by this afternoon as the low moves farther away, and the focus for precipitation will shift to areas ahead of the cold front. A line of showers and thunderstorms is forecast to develop ahead of the cold front today, and a wave of upper level energy moving over the Upper Midwest will provide support for scattered severe thunderstorm development this afternoon into tonight. The Storm Prediction Center has highlighted portions of the Upper Midwest and eastern portions of the central and southern Plains with a Slight Risk of Severe Thunderstorms (level 2/4). Potential storm hazards will include a couple of tornadoes, large hail, and damaging wind gusts. Additionally, locally heavy rain in stronger storms may result in isolated instances of flash flooding in the Upper Midwest. Showers and storms ahead of the cold front will push east into the Great Lakes region on Friday, but the front will weaken as it becomes separated from its parent low in Canada. Shower and storm chances will also linger along the eastern seaboard as a low pressure system strengthens offshore in the western Atlantic. The main low will remain parked southeast of Cape Cod over the next few days while a slow-moving cold front extends southwest to the Florida Peninsula. Strong gusty winds will be possible over the coastal waters in the vicinity of the central low, which has prompted the issuance of Small Craft and Coastal Flood Advisories along portions of the Mid-Atlantic and Northeast Coasts and Gale Warnings for the offshore waters south of Cape Cod and Long Island. This system will finally pull away from the East Coast by Sunday, which will result in decreasing winds and precipitation chances. Calmer weather is expected for the West today, with some lingering showers and storms under an upper low in the Great Basin and California, then the next round of unsettled weather will arrive with a southward moving frontal system Friday and Saturday. Precipitation will spread from the Northwest and northern Rockies south to the Four Corners Region by Saturday, and some wintry precipitation will be possible in the higher elevations of the Intermountain West. Precipitation chances will also expand again across the Plains and portions of the Midwest late Friday into Saturday as the frontal system pushes east of the Rockies. Temperature-wise, late-summer heat will stick around in the Central U.S. through the end of this week. Warm southerly flow will keep high temperatures in the 80s and 90s from the southern/central Plains to the Upper Midwest. Some areas in the southern Plains could see near record highs today and Friday as highs approach 100 degrees. Above average temperatures are also forecast for the Great Lakes and interior Northeast underneath an upper level ridge. Temperatures in the West will remain below normal over the next few days in the wake of the Plains system and the upcoming late week frontal system. Temperatures in the East and Southeast will be near normal with highs generally in the 70s and 80s. Dolan Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php