Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 404 PM EDT Mon Sep 24 2018 Valid 00Z Tue Sep 25 2018 - 00Z Thu Sep 27 2018 ...A wet pattern is expected to continue over the eastern half of the country while dry conditions will persist in the western U.S.... ...Strong to possibly severe thunderstorms expected from the Midwest to the Great Lakes Tuesday and Wednesday ahead of a strong cold front... ...Threat of excessive rain over the Ohio Valley should gradually diminish on Tuesday... The upper-level pattern across the U.S. continues to favor a wet pattern over the eastern half of the country for the next couple of days, while dry conditions will persist in the western U.S. Tropical moisture associated with a dissipating low pressure system in the southern Plains will be lifted northeastward into the Ohio Valley where heavy rain could lead to flash flooding through tonight. As the associated warm front lifts further northeastward on Tuesday, the focus of heavy rain will shift into New England as the rain becomes more scattered in nature over the Ohio and Tennessee Valleys out to the northern Mid-Atlantic. Cool and damp air will initially be trapped along the East Coast under a surface high pressure ridge. But as the warm front lifts steadily northeastward through New England Tuesday night, summery heat and humidity should return to much of the East Coast on Wednesday. A strong cold front is forecast to sweep across the central Plains and should reach the Ohio Valley and the southern Plains early on Wednesday. Thunderstorms could become severe from the Midwest to the Great Lakes Tuesday and Wednesday ahead of the front. Much cooler air from Canada will then pour into the Plains behind the strong cold front, with much below normal temperatures reaching the southern Plains on Wednesday. Meanwhile, mainly dry conditions are expected to persist across the western U.S. with an elevated to critical fire danger forecast for portions of the Great Basin, the central Rockies, and northern California. Please refer to the Storm Prediction Center for further details on the fire threat. Elsewhere, some mixed precipitation can be expected over the high elevations across the northern Rockies tonight into early on Tuesday near a stationary front. Kong Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php