Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 339 AM EDT Tue Jun 30 2015 Valid 12Z Tue Jun 30 2015 - 12Z Thu Jul 02 2015 ...Severe thunderstorms possible for portions of the Southeast, Ohio valley, and Mid-Atlantic... ...Above average temperatures continue for the Northwestern U.S... An upper-level trough and a couple surface frontal boundaries moving across the Great Lakes today will provide support for scattered showers and thunderstorms much of the eastern third of the country. A warm front moving northward across the Mid-Atlantic states will provide additional focus for showers and thunderstorms along and north of the front as it moves into the Northeast by this evening. The Storm Prediction Center is forecasting a slight risk of severe thunderstorms over a large area including portions of the Southeast, Ohio valley, and Mid-Atlantic today into tonight. Please refer to products issued by the SPC for further details on the severe weather threat. An additional area of upper-level energy will move into the northern plains late today into Wednesday, with an associated surface low pressure system forecast to develop along a west-east oriented frontal boundary extending from the central plains into the Rockies. This system will bring good chances for showers and thunderstorms to much of the central and northern plains tonight into Wednesday, with the potential for an area of widespread showers and thunderstorms Wednesday morning the middle Mississippi valley. The Storm Prediction Center is forecasting a slight risk of severe thunderstorms through tonight across portions of the northern High Plains. Across the West, the story will remain the same one that has been seen for days, with a large upper-level ridge remaining entrenched. The ridge will keep above average temperatures in place, particularly across the interior Northwest, where afternoon high temperatures of 10 to 20 degrees above average will continue through Wednesday. Low-level flow will continue to transport moisture from the Gulf of Mexico and the Gulf of California northward into the western U.S. This will be sufficient for scattered afternoon and evening thunderstorms -- most likely in areas of terrain. As has been the case for the past few days, most areas will remain dry. Ryan Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php