Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 350 AM EDT Thu Oct 19 2017 Valid 12Z Thu Oct 19 2017 - 12Z Sat Oct 21 2017 ...Heavy rainfall expected across the Pacific Northwest... ...Snow expected across the Cascades and northern Rockies... ...Scattered thunderstorms for Florida, the Southwest, and the Texas coast... ...Heavy rainfall and an enhanced risk of severe thunderstorms are possible for the southern Plains to the Middle Mississippi Valley... As a cold front dives across the Pacific Northwest today, precipitation will increase throughout that region and into the northern Rockies. Heavy rainfall is expected to occur in western Washington and northwestern Oregon where there is a marginal risk of flash flooding. In addition, higher elevation snow is expected for the Cascades in addition to the northern portions of the Sierra Nevada mountain range. As the front pushes across Intermountain West on Friday, precipitation will follow suit--with snow tamping up along the northern Rockies. Onshore flow will keep rainfall and higher elevation snow in the Pacific Northwest on Friday. By Saturday, another frontal system will begin approaching the Pacific Northwest, ensuring additional heavy rainfall and higher elevation snow once again for the region. A slow moving front near South Florida will linger over the next few days. With plenty of moisture in place from easterly flow, this front will act as a focal point for showers and thunderstorms especially in the afternoon and evening. The heaviest activity is expected along the Atlantic coast and South Florida. As an upper level trough approaches the Southwest and southern Plains, this will fire off convection across New Mexico and West Texas. In addition, southeasterly flow ahead of an approaching upper level trough along the Deep South Texas coastline will bring showers and thunderstorms to the area today. On Friday and Saturday, the moisture axis will shift to the middle and upper Texas coastlines--bringing scattered showers and thunderstorms to these areas. Meanwhile, the strong cold front that pushes across the Intermountain West is expected to sweep over the Plains on Saturday. Moisture from the Gulf of Mexico will be on tap and with instability in place--a line of showers and thunderstorms are expected to develop in the Plains. Heavy rainfall is possible from the Red River Valley to the Middle Mississippi Valley--where there is a slight risk of flash flooding. In addition, there is an enhanced risk of severe thunderstorms for North Texas and central/eastern Oklahoma. Please see the Storm Prediction Center for more information on the severe weather impacts with this system. Reinhart Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php