Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 400 PM EDT Thu Jun 09 2016 Valid 00Z Fri Jun 10 2016 - 00Z Sun Jun 12 2016 ...Pleasant weather conditions continue for one more day in the eastern U.S. before heat and humidity returns for the weekend... ...Scattered showers and thunderstorms over the western U.S... The pristine airmass currently over the eastern U.S. is expected to be in place for one more day along much of the East Coast. Cool overnight lows, mild afternoon highs, together with low humidity will make for very pleasant conditions for early June. By Saturday, the warm air mass that has been building in the northern Plains and the Midwest will spread eastward into the mid-Atlantic region, where the high temperatures on Saturday is forecast to soar back up into the low 90's with a chance of showers and thunderstorms. Hot and dry weather is forecast to continue for the central Plains into much of the Deep South with highs in the 90s and plenty of sunshine. The exceptions will be near the Gulf coast and into the Florida peninsula, as numerous showers and storms are forecast to persist near a stalled frontal boundary which is expected to nudge northward and slowly dissipate during the weekend. Out West, some residual shortwave energy trapped underneath an upper-level ridge combined with daytime heating will be enough to produce scattered showers and thunderstorms over parts of the Rockies and into the western High Plains for the rest of today. By Friday and Saturday, these showers should be confined mainly in the central and southern Rockies. Out in the Pacific, a large upper-level low will move slowly into the Pacific Northwest by Saturday. This system will bring a new round of showers and afternoon thunderstorms across the Pacific Northwest, Intermountain West, and into the Northern Rockies during the next few days. Kong Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php