Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 316 AM EDT Fri Sep 15 2017 Valid 12Z Fri Sep 15 2017 - 12Z Sun Sep 17 2017 ...Heavy rainfall along with severe weather is expected from the Northern Plains to the Upper Great Lakes... ...First snows of the season will be delivered to the highest elevations of the Northern Rockies... An amplifying upper level trough, along with a surface cold front, will move from the Intermountain West to the Great Lakes over the short term period--which will give way to precipitation across these areas. On Friday, the heaviest precipitation will occur in the Intermountain West, Northern Plains, and the Central Great Basin. There is also a slight risk of severe weather in the Northern Plains ahead of the impending cold front. With much cooler conditions settling in behind the cold front, this will aid in bringing the first snowfall of the season to the Northern Rockies. The axis of heavy precipitation will continue to shift north and east as the upper level trough takes an easterly track. By Saturday, the heaviest precipitation will move into Canada while showers and thunderstorms fire off along a surface cold front in the Upper/Middle Mississippi Valley. In addition, expect lingering showers/snowfall in the Intermountain West and Northern Rockies--albeit much lighter snowfall totals compared to Friday. By Sunday, the front will stretch from the Upper Great Lakes into the Southern Plains. This boundary will continue to act as a focal point for developing showers and thunderstorms across those regions. Farther south, moisture from the eastern Pacific Ocean will pulled across Mexico and West Texas which will generate showers and thunderstorms late Friday night/early Saturday morning. As the aforementioned cold front moves closer to the Southern Plains later on Saturday, precipitation will shift towards the Texas Panhandle and into parts of Oklahoma. Meanwhile, a weak upper level disturbance in the western Gulf of Mexico will gradually move toward the eastern Gulf Coast. This will bring an increase of showers and thunderstorms along the central and eastern Gulf Coast on Friday and Saturday. The pattern for temperatures has flipped from the previous month as now the western U.S. will generally stay below average as the upper level trough is the dominant feature. The eastern U.S. can expect above average temperatures through the short term period. High temperatures throughout the Central Plains to the Middle Mississippi Valley will reach the mid-upper 90s ahead of the cold front--although much cooler conditions will follow behind the front by Sunday. Temperatures across the interior of New England will also be 10-15 degrees above average for the weekend. Additionally, as Tropical Storm Jose approaches the East Coast, dangerous surf and rip current conditions can be expected throughout the weekend. Reinhart Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php