Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 245 PM EDT Wed Jun 15 2016 Valid 00Z Thu Jun 16 2016 - 00Z Sat Jun 18 2016 ...Severe thunderstorms possible across parts of the Great Lakes, Ohio and Tennessee valleys, and northern High Plains... ...Heavy rain possible on Thursday across portions of the Mid-Atlantic region... ...Dangerous heat expected to continue across much of the central/southern plains and Mississippi valley... A low pressure system will move across the Great Lakes tonight, bringing showers and thunderstorms to the region. A warm front extending east from this system will also bring scattered to numerous showers and thunderstorms to portions of the Ohio valley, central/southern Appalachians, and Mid-Atlantic region into tonight. Thunderstorms may become severe for some areas, and the Storm Prediction Center is forecasting a slight risk of severe thunderstorms through tonight across portions of the Great Lakes, and the Ohio/Tennessee valleys. On Thursday, the low pressure system will cross the Appalachians and approach the Mid-Atlantic, bringing another round of rain and thunderstorms from the lower Great Lakes into the Mid-Atlantic by afternoon and evening. Heavy rainfall amounts of 1 to 3 inches are possible across these areas on Thursday, and localized flash flooding is possible. Severe thunderstorms are possible across the same areas as well. Rain and thunderstorms will linger across the southern Mid-Atlantic and portions of the Carolinas into Friday morning before decreasing in coverage by afternoon as the area of low pressure moves offshore. Scattered showers and thunderstorms will continue to be possible farther west on Friday ahead of the cold front across much of the Southeast and lower Mississippi valley. High pressure at the mid and upper-levels of the atmosphere will remain locked in place across the southern and central plains through the next couple days. While a few isolated showers or thunderstorms will be possible along the dryline, most areas will remain dry and hot. High temperatures on Thursday and Friday are forecast to be 10 to 15 degrees above average across much of the central and southern plains. Heat indices may reach 100 to 110 degrees for some areas, and heat advisories have been issued for much of this region. Please refer to products issued by local NWS Forecast Offices for details specific to your area. An area of low pressure at the upper-levels will linger across the Pacific Northwest through the next couple days. This will keep somewhat unsettled conditions in place across much of the West. Areas of showers and thunderstorms will be a daily occurrence from the Northwest to the northern Rockies and portions of the northern High Plains, along and north of a stationary surface front. The Storm Prediction Center is forecasting a slight risk of severe thunderstorms through tonight across portions of the northern High Plains. Ryan Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php