Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 411 PM EDT Thu May 16 2019 Valid 00Z Fri May 17 2019 - 00Z Sun May 19 2019 ...Severe thunderstorms possible from the northern Plains to Ohio Valley tonight... ...Severe thunderstorms likely for much of the Great Plains on Friday... ...Heavy snow over the Sierra Nevada through tonight... ...Heavy rain possible for parts of the northern Rockies through tonight... ...Much cooler than normal conditions for much of the western U.S. and the northern Plains... The upper-level pattern will favor a trough of low pressure moving across the western U.S. into the Plains while a ridge of high pressure is forecast to persist over the eastern U.S. This will allow unsettled weather and chilly temperatures to continue for much of the West and into the northern Plains. The current system that is bringing widespread precipitation for the West Coast and heavy snow along the Sierra Nevada will edge its way eastward into the Great Plains by the weekend. Low-elevation rain and mountain snow will progress gradually eastward across the Great Basin and into the central and northern Rockies on Friday. As the main energy of this system reaches the Plains on Saturday, the chance of strong to severe thunderstorms will be much elevated up and down the Plains states, especially in the afternoon into the evening hours ahead of a dry line together with a developing surface low pressure center moving up along a cold front. In addition, heavy downpours associated with the thunderstorms will likely lead to flooding issues. Meanwhile, precipitation associated with the next system from the eastern Pacific is forecast to move into the West Coast on Saturday where another round of widespread precipitation appears likely. Warm and moisture air is forecast to spread eastward from the central Plains towards the eastern U.S. during the next couple of days. High temperatures in the low 90's over the central Plains this afternoon are forecast to spread eastward into the interior Mid-Atlantic by Saturday afternoon. Kong Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php