Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 344 PM EST Fri Feb 27 2015 Valid 00Z Sat Feb 28 2015 - 00Z Mon Mar 02 2015 ...Below normal temperatures to dominate much of the country... ...Multiple feet of snow expected across the San Juans and Mogollon Rim... ...A winter storm is forecast to affect an area from the Southern/Central Plains up to the Lower Great Lakes... The upper pattern across the country will continue to feature an expansive trough while a pair of ridges anchor the Eastern Pacific and Caribbean, respectively. The lack of a ridge over the U.S. should help maintain below average temperatures across a majority of the region. An arctic high moving across the central to eastern states shows a strong influence on the daily temperatures. Highs will be on the order of 25 to 30 degrees below average across the Southern and Central Plains on Saturday with the cold temperatures translating south and east in time. This generally equates to highs in the 20s and 30s while lows plummet well into the teens. Another trough deepening across the north-central U.S. will allow a cold front to swoop through the Plains helping reinforce the chilly readings through the weekend. A large-scale upper low dropping down from the Pacific Northwest toward the coast of California will bring about an extended period of unsettled conditions. Initially the more inland track this system takes will not able to tap into much Pacific moisture which should keep precipitation amounts down across the Northwestern U.S. As the trough curves out into the coastal waters of Central California, it should finally be able to draw larger amounts of moisture which will significantly augment rain/snow totals. While providing some drought relief to the California coast with a steady period of rain, forecast amounts will be rather impressive farther inland. During the next two days alone, the Mogollon Rim can expect 2 to 3 inches of precipitation. The WPC winter weather desk suggests 1 to 2 feet of this will be snow over the higher elevations. Meanwhile, during the same period, the San Juans in southwestern Colorado may see in upwards of 5 inches of precipitation which equates to several feet of snow. The long duration of the event combined with persistent moist, upslope flow should aid in producing such robust totals. Another winter storm is expected to affect sections of the Southern/Central Plains through the Middle Mississippi Valley and into the Lower Great Lakes and Ohio Valley. The vast coverage of arctic air will create a messy situation where ice, sleet, and snow are all possible. Impulses moving eastward from the trough across the West will help drive precipitation from the Great Plains eastward. Gulf moisture will gradually be on the increase with much of this milder air overriding the subfreezing surface layer. The current forecast suggests measurable ice anywhere from Texas/Oklahoma across much of the Lower Ohio valley with another separate axis along the Southern/Central Appalachians. Meanwhile, the northern extent of the precipitation shield should be all snow with the heaviest amounts likely congregating over Central Missouri up through Central Illinois/Indiana where 6 to 8 inches are possible. For more information on this threat, please read the QPFHSD on the WPC page under the header discussions. Rubin-Oster Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php