Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 325 AM EDT Sun Aug 11 2019 Valid 12Z Sun Aug 11 2019 - 12Z Tue Aug 13 2019 ...Hot and humid conditions across the South and heavy rain for parts of the central and northwest U.S. through the weekend... The upper level trough initially over the Pacific Northwest Sunday morning is forecast to cross the northern tier of the U.S. and support the development of an organized surface low over the Great Lakes and Ohio Valley region by Monday night and into early Tuesday. This will likely result in multiple rounds of heavy rain and strong to severe thunderstorms across the central and northern Plains, and extending eastward across the Midwest and northern Ohio Valley through Monday. Flash flooding will be possible with the strongest and most persistent convection, with rainfall totals of 1 to 2 inches widespread from southern Nebraska to the greater Chicago area, with locally higher amounts. Another story making weather headlines over the next couple of days will be the oppressive heat and humidity across the south-central U.S., especially from eastern Texas to Georgia. Widespread heat advisories are in effect, and some of these may be eventually upgraded to excessive heat warnings. This is in response to a strong upper level ridge anchored over the region, with highs well into the 90s and low 100s and dewpoints in the 70s, producing heat indices on the order of 105 to 115 degrees during peak afternoon heating. Elsewhere, monsoonal moisture will also continue to produce diurnally driven showers and thunderstorms through the weekend across the southern Rockies, some of which may be heavy at times, and especially over the higher terrain. Some localized flash flooding will be possible here as well, particularly over and near any burn scar locations. Across the Ohio Valley, Mid-Atlantic and Northeast, mostly dry and pleasant weather is expected going into early next week with temperatures near normal. Temperatures across northern New England should be a little below normal over the next couple of days. The next threat of rain will come late Monday across parts of the Ohio Valley as the upstream shower and thunderstorm activity over the Midwest advances farther east. Hamrick Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php