Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 358 PM EDT Tue Sep 27 2016 Valid 00Z Wed Sep 28 2016 - 00Z Fri Sep 30 2016 ...Heavy rain expected across the Mid-Atlantic region as moisture increases ahead of an anomalous upper low digging into the Ohio and Tennessee Valleys... ...Temperatures should remain above normal across the northern Rockies while scattered showers and thunderstorms will be possible over the Southwest and southern Rockies and... Cool and unsettled conditions are expected with an anomalous upper low digging southeastward through the Great Lakes...Ohio Valley...and Tennessee Valley the next few days. As the upper low slowly approaches the central Appalachian Mountains, it will be able to tap into enough moisture from the Atlantic Ocean to generate an organized area of moderate to heavy rainfall by Thursday over parts of the Mid-Atlantic and Appalachian Mountains. Elsewhere, expect cool and mostly dry conditions across much of the central U.S. and extending westward towards the Rocky Mountains courtesy of the large surface high in place. A few showers will be possible on Tuesday over the Pacific Northwest with the passage of a cold front over Washington and Oregon. Showers will also be possible over mountainous areas of Arizona and New Mexico with some monsoonal moisture in place. Gerhardt Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php