Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 347 AM EDT Sat May 14 2016 Valid 12Z Sat May 14 2016 - 12Z Mon May 16 2016 ...Below average temperatures expected for much of the central and eastern U.S. this weekend... ...Heavy rainfall possible for southern Texas and the western Gulf Coast... ...Heavy rainfall possible for northeast Oregon and northern Idaho... Showers and thunderstorms falling over New England early this morning will diminish this afternoon as the low pressure system and associated cold front moves offshore. Another cold front swinging through the Upper Midwest, Midwest and Great Lakes region today will spread showers and thunderstorms across the lower Great Lakes, Ohio valley and central Appalachians, Mid-Atlantic and the Northeast. A wintry mix and/or snow will be possible for the Upper Great Lakes area today as a much colder airmass ushers in the wake of the front - spreading to areas downwind of the lower Great Lakes and central Appalachians tonight into Sunday. Temperatures are forecast to be 10 to 25 degrees below average across a large area of the plains, Midwest, Great Lakes, and Ohio valley. The chilly temperatures will expand to the Northeast and Mid-Atlantic regions on Sunday. The southern flank of this front will push south through the southern Plains and lower Mississippi valley - likely maintaining the showers and thunderstorm activity over Texas and Oklahoma this weekend. The threat of these storms turning severe will be marginal this weekend; however, periods of heavier rainfall is expected. Excessive rainfall outlooks have been issues for this region through Monday. Showers and thunderstorms will spread into much of the interior Northwest and the northern Intermountain West as a low pressure system advances inland. Snow will be possible at the highest elevations of the central and northern Rockies by Sunday as a stationary front persists over the area and southerly flow spreads moisture into the region. The precipitation will likely focus along the stationary boundary for a long duration. This will increase the risk for flash flooding, therefore an excessive rainfall outlook has been issued for portions of northeast Oregon and north-central Idaho. Campbell Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php