Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 400 AM EDT Tue Oct 31 2017 Valid 12Z Tue Oct 31 2017 - 12Z Thu Nov 02 2017 ...Heavy snow likely over parts of the Central and Northern Rockies... ...Heavy snow possible over parts of the Northern Wisconsin and the extreme western parts of the Upper Peninsula of Michigan... ...Heavy rain possible over parts of the Western Gulf Coast... A weakening frontal boundary will drift south through the Southern Plains while the portion leading edge continues to push east today across the Southern Appalachians and Mid-Atlantic. Rain, possibly heavy at times, will focus along the portion of the boundary near the western Gulf Coast. This will increase the risk for flash flooding conditions. Snow, possibly even isolated heavy snow, is forecast for the Central Rockies . A deep upper-level low will continue to track northeastward through Wednesday. Upper-level energy over the Central Plains/Middle Mississippi Valley will move eastward around the upper-level low to Maine this afternoon then moving into Eastern Canada by Wednesday. An area of widespread light snow and rain is forecast for the Great Lakes region this morning; with lake-enhanced snow beginning over the the favored areas downstream this afternoon and persisting into Wednesday. Rain over the lower lakes is expected to taper on during the day on Wednesday. A low pressure system will slide southeast from Canada into the Northern Rockies and High Plains bringing another shot of snow to much of the Northern Rockies. Heavy snow will be likely in the higher elevations. The snow will expand into portions of the High Plains by midweek. Campbell Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php