Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 405 PM EDT Tue Apr 17 2018 Valid 00Z Wed Apr 18 2018 - 00Z Fri Apr 20 2018 ...Late season snow expected for the northern Plains into the Upper Midwest... ...Dangerous fire weather conditions expected to continue through Wednesday across parts of the southern and central Plains... Another late season snowstorm is in the forecast for parts of the Upper Midwest on Wednesday as a surface low pressure system slides eastward across the central Plains and into the middle Mississippi Valley. To the north side of this low, temperatures will be well below normal and cold enough to support accumulating snowfall. Expect snowfall to start tonight across western portions of the Dakotas tonight where accumulations of generally less than 6 inches are expected. As the associated upper level system strengthens, snowfall will ramp up across portions of the upper Midwest tomorrow. Winter storm watches, warnings, and winter weather advisories are in effect from eastern South Dakota to southern Wisconsin where a swath of 6 to 12 inches of snow is in the forecast. The surface low moves into the Ohio Valley and the Northeast on Thursday, and mainly light accumulating snowfall will spread into portions of the Great Lakes and interior New England. Near and south of the low center, rain showers and embedded thunderstorms are possible from the central Plains to the Ohio Valley on Wednesday, moving into the Mid-Atlantic and Northeast on Thursday. Due to very low relative humidity and gusty winds, the critical to extreme fire weather conditions are expected to continue into tonight for much of the southern High Plains where widespread Red Flag Warnings are currently in effect. By Wednesday, conditions should start to improve, but an elevated to critical risk remains across portions of central Texas and into Oklahoma and Kansas. See products issued by the Storm Prediction Center for more information. Elsewhere, another system moving towards the West Coast on Wednesday and inland by Thursday will bring scattered rain and mountain snow showers to parts of the Pacific Northwest, California, and the Great Basin. Moisture being pulled northward from the Gulf of Mexico will allow showers and thunderstorms to develop across parts of the southern Plains by late Thursday, which should bring much needed relief to the dangerous fire weather conditions across that region. Santorelli Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php