Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 430 PM EDT Wed Jun 18 2014 Valid 00Z Thu Jun 19 2014 - 00Z Sat Jun 21 2014 ...Showers and thunderstorms continue along the northern Rockies and into the High Plains and even high elevation snows... ...Strong to severe storms and flash flooding are possible along a boundary draped from the central Plains to the Middle Atlantic... An upper level low will slowly move northeastward out of the Intermountain West and toward central Canada. Showers and thunderstorms will continue across the Northern Rockies and central Montana into tomorrow morning, with snow possible in the higher elevations. As the upper low makes its exit, showers and thunderstorms will taper off to scattered showers tomorrow afternoon before ending in the evening. A stationary boundary draped from the Central Plains to the Mid Atlantic will be the focus for showers and thunderstorms through Thursday. A hot and humid airmass in place south of the boundary is providing plenty of energy for thunderstorm development this afternoon. Some thunderstorms could be severe. With numerous rounds of thunderstorms expected across portions of the Midwest and Ohio Valley flash flooding will be a threat. The severe weather threat will be more focus tomorrow ahead of a cold front pushing through the Central Plains. With high pressure in place across the Southeast for the next few days, the heat and humidity will continue from the Southern Plains to the Mid Atlantic. Heat indices will near 100 across much of the area. Krekeler Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php