Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 440 PM EDT Sat Mar 21 2020 Valid 00Z Sun Mar 22 2020 - 00Z Tue Mar 24 2020 ...Heavy Snow for the Sierra, Cascades and Central Rockies... ...Wet weather to spread northeastward from the Southern Plains/Lower Mississippi Valley into the Ohio Valley/Mid-Atlantic... ...Below average temperatures for the Mississippi Valley and Northeast... A low pressure system will arrive at the California coast on Sunday evening bringing heavy snow to the Sierra and rainfall to the lower elevations. Snowfall accumulations in excess of a foot are likely for the Sierra through Sunday while up to 2 inches of rain is probable for parts of southern California. The Central Rockies will receive 4-8 inches of snow on Sunday from this system. At the same time, another low pressure system will descend over the Pacific Northwest from the Canadian Meritime. Snow totals between 4-8 inches are expected across the Cascades and Olympics with locally higher amounts possible at the highest peaks. Meanwhile to the east, an area of low pressure will develop along the lee side of the Rockies Sunday morning and begin moving eastward. This system will produce 1-2 inches of rain for a swath of real estate extending from the Southern Plains into the Mid-Atlantic through Monday. Snow will fall on the north side of the low from northern Pennsylvania through southern New England. There's a high probability of heavy snow impacting the Catskills and southern Adirondacks on Monday with accumulations likely to be between 3-6 inches. An upper-level ridge will build in behind the eastern U.S. system which will lead to high temperatures dropping 15-20 degrees below average for much of the Mississippi Valley on Sunday. Surface high pressure will extend back across the Northeast while the area of low pressure moves off the Deleware coast on Monday. This will lead to a cold air damming event over the interior Northeast as high temperatures will be 15 to 20 degrees below normal as a result. Kebede Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php