Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 306 AM EDT Wed Jul 15 2015 Valid 12Z Wed Jul 15 2015 - 12Z Fri Jul 17 2015 ...Showers to diminish across the East followed by cooler, drier conditions from the Midwest, Ohio valleys and Northeast... ...Hot and humid conditions will remain across the southern tier of the US while moisture continues north northeastward from the Southwest and Rockies across the Central and Northern Plains, where some of the heaviest thunderstorms are expected the next couple days... ...Cooler conditions will also make an entrance across the Northwest with the passage of a cold front... The slow moving upper trough over the Ohio Valley and East will continue drifting eastward as showers begin to diminish from west to east across the Mid Atlantic and Northeast states. A rather sharp cold front has dropped temperatures across parts of the Midwest and northern New York tonight and spells some cooler and drier air that will be making its way south and eastward across much of the eastern third of the country, with the exception of the Gulf Coast and Florida. Tuesday morning temperatures will be in the 40s and 50s in the Midwest and interior New York. Meanwhile, a series of weak disturbances within a broad upper trough over the West will move eastward and will help generate some heavy thunderstorms across portions of the Central and Northern Plains as well as the Upper Mississippi Valley. The storms will develop along and ahead of a developing warm front over the Central Plains that will drift northeastward toward the Midwest toward Thursday night and Friday morning. Locally heavy rains are anticipated for portions of eastern Nebraska, Iowa and southern Minnesota, as well as across North Dakota. Hot and humid conditions will build slowly northward across the Southern and Central Plains toward the Mid Mississippi Valley over the next couple days. A developing cold front over Southwest Canada will begin pushing south and eastward and should have crossed much of the state of Montana into western North Dakota by Friday morning. Cooler temperatures are expected behind the front. Meanwhile, monsoonal moisture will produce scattered showers and thunderstorms especially across elevated portions of the Southwest into the Rockies, especially on Tuesday. Kocin Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php