Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 256 AM EST Thu Dec 29 2016 Valid 12Z Thu Dec 29 2016 - 12Z Sat Dec 31 2016 ...Significant winter storm likely to impact interior New England through Friday... ...Showers and thunderstorms possible from the Deep South to the Mid-Atlantic today... ...Another round of rain and mountain snow is possible for the Pacific Northwest and the Intermountain West... Much of New England will be impacted by a rapidly developing winter storm today and will continue into the weekend. Lake effect snow warnings are in affect for areas downwind of the Great Lakes, with numerous winter storm warnings and winter weather advisories spanning from northeast Pennsylvania/eastern New York to Maine. Heavy snow will begin by this afternoon and continue into Friday - storm total accumulations of a foot or more will be possible for locations along the Adirondacks to western Maine. Gusty winds will also accompany this storm; which will create poor travel conditions. Cold air will usher into the region on the backside of the low and will generate enhanced heavy snowfall for the favored downwind areas of lakes Erie and Ontario. Additionally, accumulating snow is also expected along favorable upslope regions of the central Appalachians. Rain and thunderstorms will spread east across the Deep South, Southeast and the Mid-Atlantic today as the southern flank of the front moves through. Localized areas of heavy rainfall will be possible, especially along the boundary itself and within thunderstorms. Temperatures are expected to return to near normal or slightly cooler than average as surface high pressure builds in. A Pacific cold front will move inland today and track eastward though the Intermountain West and into the Northern Plains/Upper Midwest Friday and Saturday. Rain and mountain snow will accompany this system. The higher elevations of the Cascades, northern Idaho and western Montana may have periods of heavier snow fall. Gusty winds will accompany this system as it cross the Rockies - high wind warnings are in effect for portions of northern Montana and the Big Horn Range in Wyoming. Prior to the frontal passage, much of the Central and Northern Plains will have warmer than seasonal average temperatures. Afternoon highs of 10 to 20 degrees above normal on are forecast for Friday. In the Southwest, precipitation chances increase into Friday as an upper level low approaches the southern California coast. Campbell Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php