Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 345 AM EDT Tue Mar 17 2015 Valid 12Z Tue Mar 17 2015 - 12Z Thu Mar 19 2015 ***Colder weather arriving for much of the country*** ***Unsettled weather to affect the Northwest U.S.*** ***Scattered showers and thunderstorms for the southern Plains*** After a few days of warm weather across much of the central and eastern U.S., things will be changing on Tuesday as a strong cold front ushers in a much colder air mass for the middle of the week. The surface high behind the front will bring below normal temperatures by mid-March standards, with highs in the 40s widespread from the Midwest to the Mid-Atlantic region. For the western U.S., a series of weak disturbances aloft and a surface cold front working its way across the Intermountain West will generate patchy areas of rain from the Pacific Northeast to the northern Rockies. Given the lack of deep moisture with this system, rainfall amounts are expected to be generally light with snow confined to the highest elevations and north of the border in Canada. Another area of precipitation worth mentioning will be moisture increasing over Texas and New Mexico from a trough and upper level low situated over Mexico. Significant rainfall is likely over central and eastern Texas by Tuesday night and Wednesday as a wave of low pressure develops along the cold front that passes through the eastern U.S., which will intersect the moisture flowing northward from the Gulf of Mexico. Hamrick Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php