Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 430 AM EDT Thu May 27 2021 Valid 12Z Thu May 27 2021 - 12Z Sat May 29 2021 ...A low pressure system will bring strong to severe thunderstorms from the central Plains eastward toward the central/southern Appalachians into Friday... ...The same low pressure system will bring moderate to heavy rain for parts of the Northeast and possibly severe thunderstorms for the Mid-Atlantic toward the Memorial Day weekend... A developing low pressure system currently in the central High Plains will be the main weather maker for the central and eastern U.S. as we head into the Memorial Day weekend. Showers and thunderstorms will generally expand eastward into the Midwest today ahead of the low pressure center while additional thunderstorms are expected to organize across the central Plains ahead of a cold front. Some of these thunderstorms are expected to become severe. In addition, heavy downpours from the thunderstorms could result in flash flooding. Much of the rain and thunderstorms will be moving across the lower Great Lakes, Midwest, Ohio and Mid-Mississippi Valleys, and toward northeastern Texas on Friday. By later on Friday, the low pressure system is forecast to move across the central Appalachians. Thunderstorms developing over the Mid-Atlantic could become severe later on Friday. Meanwhile, moderate to heavy rain is forecast to develop across southern New England early on Saturday as a new low pressure center is forecast to form off Long Island. Across the Deep South, scattered thunderstorms will move slowly southward toward the Gulf Coast in association with the cold front later on Friday into the Memorial Day weekend. Across the Northeast, cooler air behind a cold front will settle into the area today. Much of the northern Great Plains into the Midwest will have cool afternoons due to clouds and rain tracking to the north of the developing low pressure system. In fact, parts of North Dakota could see some wet snow early this morning. Out in the Pacific Northwest, a low pressure system moving onshore Thursday morning will bring widespread rain to the area. Mixed precipitation and even some wet snow is possible in the northern Cascades. As the system moves inland, mixed precipitation is expected for the northern Rockies early on Friday. By Friday night into Saturday morning, showers and some thunderstorms are forecast to move across the northern Plains ahead of a front, while a new low pressure center is forecast to develop in the central High Plains. Kong Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php