Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 355 AM EDT Thu Jul 5 2018 Valid 12Z Thu Jul 5 2018 - 12Z Sat Jul 7 2018 ...Heatwave abates across the eastern U.S. whilst building in intensity for the western U.S... Expect areas of showers and thunderstorms to continue along a cold front as it tracks southeastward across the Great Lakes, Ohio Valley, and the Northeast. By Friday, much of the heavy rainfall threat will be focused across the Mid-Atlantic region as this cold front arrives and interacts with the very humid airmass in place. The front will also herald an end to the recent eastern U.S. heat wave as a quality airmass moves in behind the front in time for the weekend, with highs in the 70s and 80s and significantly lower humidity levels. Meanwhile, plenty of moisture is expected to remain in place across much of the Gulf Coast region through Friday and this will support numerous showers and thunderstorms during the afternoon and evening hours. Across the Western U.S., the upper level ridge will be building and a big heat wave is coming to the Desert Southwest over the next couple of days. High temperatures are expected to reach into the 110s over the lower elevations of southern California, southern Nevada and Arizona as the upper level ridge builds over the region. This will increase the potential for wildfire conditions given the very low relative humidities. Most of the West should generally stay dry going into the early part of the weekend, but there will gradually be some monsoonal moisture at least attempting to lift up across the Four Corners region by Saturday. As a result, isolated to scattered afternoon storms will be possible over the southern Rockies. D. Hamrick Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php