Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 349 PM EDT Fri May 17 2024 Valid 00Z Sat May 18 2024 - 00Z Mon May 20 2024 ...Unsettled weather with chances for excessive rainfall and severe thunderstorms continues across the Southeast through Saturday... ...Active weather and thunderstorm chances also exist across the northern Plains tonight before returning to the central Plains on Sunday... ...Sweltering heat continues across South Florida and builds into the southern High Plains this weekend... A continued risk of thunderstorms and areas of heavy rain are impacting parts of the Gulf Coast and Southeast this afternoon after a very wet and stormy 24 hours for the region. Additional instances of heavy rain and damaging wind gusts are possible from the central Gulf Coast to southern Georgia tonight, highlighted by a Slight Risk (level 2/5) of severe thunderstorms as well as a Moderate Risk (level 3/4) of excessive rainfall. A frontal boundary lingering from the Southeast to the north-central Gulf of Mexico on Saturday will lead to newly developing thunderstorms with the potential for more chances of flash flooding and damaging wind gusts. Areas of heavy rain and wet weather are also forecast to continue into Saturday across the Mid-Atlantic and central Appalachians, where scattered instances of flash flooding are possible. By the end of the weekend outdoor activities should become more desirable as shower and thunderstorms chances diminish for most locations in the Southeast and Mid-Atlantic due to frontal boundaries shifting offshore. Other notable areas of precipitation include the northern Plains tonight and central Plains on Sunday. An initial low pressure system churning over south-central Canada this evening with an attached cold front progressing across the northern Plains will allow for developing quick-moving showers and thunderstorms. By Sunday, the upper-level pattern reloads with troughing digging into the northern Great Basin and strong southerly flow throughout the Plains. This will allow for thunderstorms to form over the central High Plains and spread east during the evening hours. The Storm Prediction Center highlights the greatest chances for severe weather across parts of Nebraska and Kansas, with a Slight Risk (level 2/5) of severe thunderstorms issued. Otherwise, dangerous heat remains across parts of South Florida this weekend, while anomalous heat builds into much of the Plains and Midwest as well. High temperatures in South Florida are forecast to reach the mid-90s, with high humidity leading to heat indices into the triple digits. Above average temperatures this weekend will also stretch from the southern Plains to the Midwest and Great Lakes. Highs are anticipated to range from 10 degrees above average to near 20 degrees above average for the upper Great Lakes on Saturday. Afternoon max temperatures should reach the 80s and low 90s for these regions, with triple digits along the Rio Grande Valley and southern High Plains. Snell Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php