Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 331 PM EDT Fri Jun 12 2015 Valid 00Z Sat Jun 13 2015 - 00Z Mon Jun 15 2015 ...Severe thunderstorms and flash flooding possible from portions of the southern plains to the Northeast... ...Above average temperatures expected to continue for much of the western U.S. and East Coast... A frontal boundary is draped across much of the central and eastern U.S. this afternoon, extending from the southern plains to the Great Lakes and into the northern Mid-Atlantic states. A wave of low pressure along the front will cross the Northeastern U.S. tonight, with rain and thunderstorms common in association with this system. The area of low pressure will move offshore Saturday morning with a weak cold front passing through the Northeast, bringing drier conditions. Westward along the front, numerous weaker waves of low pressure will spark the development of areas of showers and thunderstorms across much of the southern and central plains into the Ohio valley. Severe thunderstorms are possible across portions of the southern plains as well as areas from the Ohio valley to the Northeast. Refer to the Convective Outlook products issued by the Storm Prediction Center for further details on the severe weather threat. In addition to severe weather, flash flooding will also pose a threat in the same areas. Farther south, scattered showers and thunderstorms will affect the central and western Gulf Coast over the next couple days as a very moist and unstable air mass remains in place. A cold front will move eastward across the Rockies tonight and into the northern plains on Saturday. Low-level moisture in association with this system will not be particularly impressive, therefore generally scattered showers and thunderstorms are expected. Across the West, high pressure at the mid and upper-levels will promote average to above average temperatures through Saturday. Daytime temperatures across interior northern California into northwestern Nevada are expected to reach 10 to 15 degrees above average. Above average temperatures will continue as well for portions of the East Coast on Saturday, where afternoon high temperatures of 5 to 10 degrees above average are expected. Ryan Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php