Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 339 AM EDT Fri Oct 05 2018 Valid 12Z Fri Oct 05 2018 - 12Z Sun Oct 07 2018 ...Heavy rain possible from parts of the Southern High Plains northeastward to the Great Lakes/Western Ohio Valley... ...Snow possible over the highest elevations of the Northern/Central Rockies... ...Temperatures will be 10 to 20 degrees below average over parts of the Northern Plains into the Upper Great Lakes/Upper Mississippi Valley... A front extending from the Mid-Atlantic westward to the Central High Plains will have a wave of low pressure over the Central High Plains that will move northeastward to Southeastern Ontario by Saturday evening. The front will also advance southward to from the Southern High Plains to the Great Lakes by Saturday evening. Showers and thunderstorms will develop along and near the boundary over parts of the Western Ohio Valley to the Central Plains on Friday morning. On Friday, the showers and thunderstorms will expand eastward along the front from parts of the Ohio Valley into the Mid-Atlantic by Friday evening. Overnight Friday as the boundary moves out of the Rockies onto the Plains, showers and thunderstorms will develop along and ahead of the cold front extending from the Southern High Plains northeastward to the Middle Mississippi Valley/Upper Great Lakes that will move southeastward to the Lower Great Lakes to the Southern Plains by Saturday evening into Sunday. In addition, upper-level energy over the Upper Mississippi Valley will move eastward into Canada while weakening by Friday evening. The energy will aid in producing rain over parts of the Upper Mississippi Valley into parts of the Middle Mississippi Valley that will move into the Great Lakes by Friday evening. Another area of upper-level energy over the Northern Rockies will move northeastward to near James Bay by Saturday evening into Sunday. Rain will develop over parts of the Northern High Plains southwestward into the Great Basin with snow over the highest elevations of the Northern Rockies that will dissipate over the Central Plains overnight Friday. Rain will move from the Upper Mississippi Valley into the Great Lakes/Ontario by Sunday. Meanwhile, upper-level energy just off the Pacific Northwest Coast will move southeastward to Eastern California/Great Basin by Saturday evening. The energy will aid in developing rain over parts of the Pacific Northwest Coast on Friday morning that will expand inland to parts of the Northern Intermountain Region by Friday evening. Overnight Friday the rain will continue to move inland over parts of the Great Basin/Northern California into parts of the Central Rockies by Saturday evening. Snow will develop over the highest elevations of the Northern Rockies overnight Friday into Saturday. Snow will also develop over some of the highest elevations of the Central Rockies by Saturday evening. Elsewhere, onshore flow out of the Western Gulf of Mexico will aid in producing showers and thunderstorms over parts of the Western/Central Gulf Coast Friday into Saturday evening. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php