Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 340 AM EDT Fri Jun 12 2015 Valid 12Z Fri Jun 12 2015 - 12Z Sun Jun 14 2015 ...Severe thunderstorms and flash flooding possible for portions of the southern Great Plains to the Northeast... ...Above average temperatures expected to continue for much of the western U.S. as well as the Mid-Atlantic and Northeast... On Friday, showers and thunderstorms will continue to spread east ahead of a low pressure system moving out of the mid Mississippi valley. Supported by very moist and unstable air emanating from the Gulf of Mexico, these storms may become strong to severe and could produce heavy rains across portions of the lower Great Lakes, Ohio valley and the Northeast on Friday. Refer to the Convective Outlook products issued by the Storm Prediction Center for further details on the severe weather threat. In the wake of this low pressure system, a trailing stationary frontal boundary extending back into the southern plains will remain a focus for shower and thunderstorm development as well. Strong to severe thunderstorms and flash flooding will also be possible across portions of this region also, especially by Friday afternoon across the Texas Panhandle into western Oklahoma, where thunderstorms development appears most likely. Across the West, high pressure at the mid and upper-levels will promote average to above average temperatures through Saturday across much of the western U.S. Daytime temperatures across interior northern California into northwestern Nevada are expected to reach 10 to 15 degrees above normal. Above normal temperatures will continue as well for portions of the Ohio valley and Mid-Atlantic into the Northeast on Friday -- where afternoon high temperatures will be 5 to 10 degrees above average. Pereira Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php