Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 336 PM EDT Wed Jul 08 2015 Valid 00Z Thu Jul 09 2015 - 00Z Sat Jul 11 2015 ...Flash flooding possible for several areas including the southern plains to the Ohio valley, portions of the Colorado High Plains and Front Range, and the higher terrain of northern California and Nevada... ...Severe thunderstorms possible across portions of the Mid-Mississippi and Ohio valleys and the southern High Plains... ...Above average temperatures for the Pacific Northwest... An area of low pressure will move from the middle Mississippi valley this evening into the Lower Great Lakes Thursday morning, and into the northern Mid-Atlantic region Thursday afternoon. An area of widespread showers and thunderstorms is expected to accompany this system as it moves eastward, moving into the Ohio valley tonight and into the Mid-Atlantic and Northeast on Thursday. Locally heavy rainfall may result in the potential for flash flooding over some of these areas, particularly across portions of the middle Mississippi and Ohio valleys and the central Appalachians. Severe thunderstorms are also possible across portions of the Mid-Mississippi valley and Ohio valley. Please refer to products issued by the Storm Prediction Center for further details on the severe weather threat. The cold front trailing the low pressure system will become stationary across the southern plains and begin to move northward as a warm front. Additional showers and thunderstorms may develop along this front across the southern/central plains on tonight into Friday. Severe thunderstorms are possible through tonight in association with this front across the southern High Plains, with flash flooding also possible for the High Plains and portions of the Front Range in Colorado. Scattered showers and thunderstorms will be possible across much of the Intermountain West, with the most widespread showers and thunderstorms expected in areas of terrain, where vertical motion will be aided. An upper-level low moving into California from the Pacific will also enhance shower and thunderstorm activity across the Sierra, Klamath, and Northern Coast ranges. Heavy rainfall may result in the potential for flash flooding for some of these areas. Meanwhile, high pressure at the mid and upper-levels of the atmosphere will persist across the Pacific Northwest, north of the upper-level low. This will keep temperatures 10 to 15 degrees above average across portions of the Pacific Northwest. Temperatures may begin to decline some by Friday as the ridge of high pressure weakens. Ryan Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php