Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 258 AM EST Fri Nov 22 2013 Valid 12Z Fri Nov 22 2013 - 12Z Sun Nov 24 2013 ***Arctic front will bring coldest weather so far this season*** ***Active weather pattern over the Southwestern U.S.*** A highly amplified upper level flow pattern will allow for a large trough to build over the Central and Eastern U.S. through the end of the week and into the weekend. A strong Arctic cold front will move southeastward from the Northern Plains to the Gulf Coast, with a secondary surge of Arctic air entering the Northern U.S. by the weekend. A huge surface high behind the front will bring widespread sub-freezing high temperatures from the Great Plains to the Ohio Valley, and lows in the single digits and teens. It will also turn sharply colder into Texas and the Deep South by the weekend after the cold front clears the region. It will be mild along the East Coast through Friday before the front approaches. The weather will be active from the Desert Southwest to the Southern Plains as the cold front settles southward. A concentrated area of moderate precipitation is expected to develop over the Four-Corners region by Friday as a pronounced upper level low forms near Southern California. Deep moisture transport ahead of this feature, interacting with the surface front, will allow for periods of rain for the lower elevations of Arizona and New Mexico, and snow for Utah and into Colorado. Elsewhere, a band of showers and thunderstorms is likely to develop near the cold front over southern Texas and the Deep South, and onshore flow over Florida will help generate isolated showers along the East Coast of that state. Sleet and freezing rain is likely for much of central and western Texas, along with parts of Oklahoma, as a shallow layer of cold air surges under a warmer layer aloft. D. Hamrick Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php