Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 359 PM EDT Wed Aug 07 2019 Valid 00Z Thu Aug 08 2019 - 00Z Sat Aug 10 2019 ...Threats for severe weather and heavy rainfall ahead of cold fronts sweeping through the Great Lakes and Northeast... ...Multiple rounds of heavy rain with potential for flash flooding from portions of eastern Kansas into Missouri... ...Relief from the heat for the Northwest while Heat Advisories remain across portions of the south-central U.S... Scattered to numerous thunderstorms located ahead of a cold front moving through the central Appalachians and Northeast this evening will continue to shift east overnight with dwindling threats for severe weather and heavy rain. Until then however, several strong to severe thunderstorms can be expected from lower New England into eastern North Carolina. The cold front will weaken as it moves off of the Mid-Atlantic and southern New England coast on Thursday with slightly lower humidity in its wake. A second cold front will approach from the north and west on, bringing threats for diurnally enhanced thunderstorms, some of which could be severe and contain heavy rain, from the Upper Midwest today into portions of the Ohio Valley on Thursday. Anomalous moisture in the vicinity of a stalled frontal boundary stretching from southern Tennessee to the western Kansas/Oklahoma border, combined with favorable lower and upper level winds, will promote a heavy rain threat tonight from eastern Kansas into western Missouri. There is a Moderate Risk of flash flooding through Thursday morning across eastern Kansas and a good chance for 3+ inch rainfall totals from portions of eastern Kansas into southwestern Missouri through late Thursday morning. A second round of heavy rain, though perhaps a bit south of tonight's expected round, is anticipated across some of the same locations, likely impacting northeastern Oklahoma into northwestern Kansas Thursday night into Friday morning. Given locally heavy rain which fell across parts of Kansas and Missouri earlier today and the multiple rounds expected, flooding and flash flooding will be a threat. The approach of an upper level trough will bring an end to the triple digit heat in eastern Washington and Oregon beginning Thursday. While highs are still forecast in the 90s across Washington on Thursday slightly cooler temperatures are forecast for Oregon and by Friday, high temperatures are expected to be near to below average across much of the western U.S. Meanwhile across the south-central U.S., hot and humid conditions will remain at least the next couple of days beneath the influence of an upper level ridge. Heat index values from southern Oklahoma into Texas, Arkansas and Louisiana are forecast to peak in the 105 to 115 degree range through Friday. Across the Southwest, monsoonal moisture will continue to result in diurnally driven showers and storms from the Four Corners into the Rockies with locally heavy rainfall possible. Otto Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php