Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 350 PM EDT Wed May 13 2015 Valid 00Z Thu May 14 2015 - 00Z Sat May 16 2015 ***Cooler pattern for the Northeast.*** ***Heavy rain and storms for the Plains*** ***Unsettled weather across the western U.S.*** A dry Canadian high pressure system will settle across the Northeast tonight, and a backdoor cold front migrates across New England on Thursday and the Delmarva on Thursday night---keeping cooler temperature readings in place across much of the Northeast US into Friday morning. The Plains and western Gulf Coast should continue to receive a succession of widespread rain and thunderstorm events---with the activity gradually spreading into the Missouri Valley and northern high Plains by Friday afternoon-evening. Heavy rainfall and potential flood threat will continue to be a major concern in portions of Texas and Oklahoma---with an additional 1-3 inches of rainfall possible during the next 48 hours. Out west, a deep and active upper-level trough will migrate across the coast and anchor in the central Great Basin during the next 36 to 48 hours. Showers and isolated thunderstorms are expected to migrate through the base of this trough---and direct a series of mid-level disturbances across central and southern California---into the Four Corners region---and then northward into the northern Rockies of Idaho, Montana and Wyoming. Higher precipitation totals are expected along the southwest Montana and northwest Wyoming border---where several inches of rain should be observed during the next 48 hours. Accompanying these mid-level disturbances---snow and snow showers for the higher elevations of the Sierra, Wasatch, the San Juans of southwestern Colorado and Tetons of Wyoming. Vojtesak Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php