Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 350 AM EDT Fri Oct 25 2013 Valid 12Z Fri Oct 25 2013 - 12Z Sun Oct 27 2013 ...High pressure and cooler temperatures for the eastern half of the country... ...Rain showers or thunderstorms possible from the Four Corners into the Southern Plains... An expansive surface high pressure anchored in the eastern half of the nation will keep temperatures very cool through the weekend with values expected to be below normal for this time of the year. Northwest of the high in Central Canada, a clipper system will continue to drop down towards the Great Lakes region by Saturday morning. Very widely scattered lake-effect rain showers are possible on Friday, with the chances for precipitation increasing as the system gets closer. Most of the precipitation should be more of a cold rain, but some mixing of snow cannot be ruled out, especially during the overnight hours of Saturday and into early morning on Sunday. Meanwhile, out west, the upper level ridge over Western Canada should keep most of the region dry and mild through the weekend. The exception to this will be across the Four Corners region where weak energy aloft could trigger some light rain and higher elevation snow showers for the area on Friday and into Saturday. By Saturday, the precipitation will begin moving into the Southern Plains and return flow off the Gulf of Mexico should increase the chances for isolated to scattered showers and thunderstorms for parts of Texas and Oklahoma. Monarski Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php