Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 424 PM EDT Mon Apr 25 2016 Valid 00Z Tue Apr 26 2016 - 00Z Thu Apr 28 2016 ...An active Spring weather pattern from the Intermountain west and into the Plains... ..Heavy snows possible over portions of the Great Basin into the Central Rockies... ...Severe weather, heavy rains and possible flooding across portions of the Central to Southern Plains and lower Missouri Valley... A very active Spring weather pattern will continue across large portions of the nation over the next several days. The atmosphere is stuck in a pattern characterized by systems deepening over the Great Basin and Rockies and then spreading east northeastward into the Plains. The lead system in this pattern continues to weaken over the Great Lakes region early this period and will then race eastward along the strong west to east front draped across the northeastern U.S. Moderate to isolated heavy rains possible from the Great Lakes into the northern Mid Atlantic and New England...while thunderstorms may affect the Mid Atlantic into the Ohio Valley. In the wake of this low moving offshore of the northeast Tuesday...low level cold air will press quickly southward through the Mid Atlantic...bringing an end to the current warm temperatures. The next amplifying system over the Great Basin/Southern to Central Rockies region will support the potential of late season heavy snows over portions of the Great Basin and Central Rockies tonight---continuing into early Wednesday. At the same time---increasing moisture---instability and lift along and ahead of the associated cold front/dry line pushing into the Southern and Central Plains and toward the lower Missouri Valley will support a broad region of thunderstorm potential---with heavy rains---flash flooding and severe weather possible across these regions Tuesday and Wednesday. Meanwhile---a frontal boundary pushing eastward from the eastern Pacific will bring increasing precipitation chances late Tuesday into Wednesday from the Pacific Northwest into large portions of California. Low elevation rains and higher elevation snows possible with this system. This system will be following the overall evolution of the earlier system that is forecast to move out of the Great Basin/Rockies region early this period---with a potential for a repeat of the current expected weather over the Rockies/Plains late this week into this weekend as this next system then pushes eastward. Oravec Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php