Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 358 PM EDT Fri Jul 27 2018 Valid 00Z Sat Jul 28 2018 - 00Z Mon Jul 30 2018 ...Severe thunderstorms and excessive rainfall possible across portions of the Mid-Atlantic and the Northeast through tonight... ...Severe thunderstorms, including the potential for tornadoes, and excessive rainfall possible for portions of the Central and Southern Plains through tonight... ...Dangerous heat to continue across the Southwest and California through Saturday... Another front is now nearing the Atlantic Coast, with showers and thunderstorms developing along the frontal boundary. Given the warm and humid airmass still in place, conditions are favorable with the approaching front for severe thunderstorms and heavy rainfall. The Storm Prediction Center has placed much of the coastal Mid Atlantic and Northeast in a Severe Thunderstorm Watch through late this evening, with a slight chance of severe thunderstorms continuing through the night as well. The Weather Prediction Center has also placed this area in a slight risk for excessive rainfall. This front will slow and stall along the Atlantic and Gulf of Mexico coasts through the weekend, allowing continued chances for showers and thunderstorms in these areas. Multiple disturbances in the upper levels will interact with a stationary frontal boundary in place from the central/southern Plains back into the central Rockies. This will result in widespread showers and thunderstorms across the Central Plains through Saturday. With plenty of moisture and instability in place, storms will be capable of producing severe weather and heavy to excessive rainfall. The Storm Prediction Center has highlighted portions of the central High Plains within a slight to enhanced risk for severe weather. A smaller area encompassing eastern Kansas, far southwest Nebraska, and far northeast Colorado has been upgraded to a moderate risk of severe weather through tonight. A tornado watch has also been issued for this same area through this evening. Large hail, damaging winds and isolated tornadoes are all threats in this region. WPC has also highlighted portions of this same region as well as into Oklahoma within a marginal to slight risk for excessive rainfall/flash flooding on Friday and Saturday. A dangerous heat wave will continue out west through Saturday underneath of a stubborn upper level ridge. Temperatures across portions of the Desert Southwest and California are forecast to be in the triple digits, which is as much as 5 to 10 degrees above normal. Excessive heat warnings and heat advisories remain in effect across interior and southern California, far northwest Arizona, and southern Nevada. Furthermore, another heat wave is expected across the Pacific Northwest, with highs forecast to be in the low to mid 90s for Sunday into Monday. An Excessive Heat Watch is in place across this area. Because of the very hot and dry conditions, fire weather and poor air quality will also remain a concern across the western U.S.. Wix Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php