Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 323 PM EDT Fri Apr 18 2014 Valid 00Z Sat Apr 19 2014 - 00Z Mon Apr 21 2014 ...Heavy rainfall likely across the Southeastern U.S. through Saturday... ...Light to moderate rainfall across the northern tier of U.S.... ...Scattered showers and thunderstorms for Southwest... Heavy rain will continue moving slowly northeastward up the Southeast coast through Saturday. A strong southerly low level jet will transport tropical moisture into a region of broad vertical motion in the mid and upper levels. This will lead to a rather large area of moderate to heavy rainfall. Strong high pressure downstream of the surface low will act to slow the eastward progression of this system. Some thunderstorms could be severe this afternoon across Florida. A series of mid level shortwaves will move across the northern tier of the U.S. bringing light to moderate precipitation to the Pacific Northwest, Northern Plains, and Great Lakes. A cold front pushing across the Northern Plains today will reach the Great Lakes by tomorrow morning. Cold air in place over northern Minnesota will lead to a period of snow tomorrow morning before warmer air overspreads the region. An approaching mid level shortwave combined with favorable position with respect to a nearby upper level jet will lead to widespread scattered showers and thunderstorms for Saturday in the Southwest U.S. The shortwave will push out over the Southern Plains by Sunday with shower activity over the Southwest coming to an end. Krekeler Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php