FXUS01 KWBC 160715 PMDSPD Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 314 AM EDT Fri May 16 2025 Valid 12Z Fri May 16 2025 - 12Z Sun May 18 2025 ...Severe thunderstorm outbreak expected today across the mid-Mississippi, Tennessee and Ohio Valleys, along with the potential for heavy rain and flash flooding... ...Multiple rounds of thunderstorms and heavy rain over the next few days could lead to isolated flash flooding across portions of New England... ...Record-breaking heat forecast across South Texas, the Gulf Coast, and Southeast through early this weekend as highs soar into the upper 90s and triple digits... ...Windy and cool conditions anticipated across the Northern Plains today, as well as the Intermountain West and Rockies this weekend... A very active and complex mid-May weather pattern is set to produce numerous areas of severe weather, heavy rain, high winds, and anomalous temperatures through this weekend. A waffling frontal boundary stretching from the mid-Mississippi Valley to the mid-Atlantic is expected to become the focus for a potentially damaging severe weather outbreak today as a sweeping secondary cold front pushes eastward out of the Great Plains tonight. Blossoming severe thunderstorms will be capable of containing large hail, damaging winds, and tornadoes between southeast Missouri and West Virginia, with thunderstorms containing damaging winds also possible across a larger area extending from northeast Texas to the mid-Atlantic. The Storm Prediction Center has issued a Moderate Risk (level 4/5) for severe weather centered over the Lower Ohio Valley, where the greatest concerns exist for several strong tornadoes. Additionally, thunderstorms in this region will be capable of containing intense rainfall rates and could lead to scattered instances of flash flooding. A Slight Risk (level 2/4) of Excessive Rainfall has been issued for this region. Residents and travelers are advised to remain weather aware by having multiple ways of receiving warnings and know where the nearest storm shelter or safe place is should severe thunderstorms approach. Elsewhere across the Northern Tier today, a strong wound-up low pressure system churning over the Northern Plains is forecast to produce additional rainfall and gusty winds across the Dakotas, with windy conditions extending further into the Midwest. High Wind Warnings and Wind Advisories are in effect. As this low pushes a few frontal boundaries eastward, a moist airmass situated over the Northeast will allow for developing thunderstorms over the next few days from the Interior Northeast to northern New England. Some thunderstorms will be capable of containing intense rainfall rates, which could lead to areas of flash flooding. A Slight Risk of Excessive Rainfall has been issued for portions of Maine today. The other primary weather story during the short term will be the anomalous early-season heat forecast from South Texas to the southeastern United States. Warm southerly winds and limited cloud cover will allow for highs to reach near record-breaking territory and well into the 90s, with triple digits expected for parts of South Texas. This is forecast to produce widespread Major to Extreme HeatRisk through this weekend across much of southern Texas, which equates a level of heat that can affect anyone without effective cooling and/or adequate hydration. Be sure to follow proper heat safety to stay cool during this first major heat wave of the season. Above average temperatures with highs into the upper 80s and 90s are also forecast today from the Midwest to East Coast, but will be short-lived as a cold front brings temperatures closer to average by this weekend. For this weekend, active weather is forecast to remain over the central/southern Plains while also overspreading this Intermountain West. A lingering frontal boundary over the southern Plains on Saturday will lift northward by Sunday and help spark several rounds of thunderstorms throughout the region. Some storms may turn severe and produce damaging winds, hail, and heavy rain. Meanwhile, a separate storm system entering the West of Saturday will spread gusty winds and showers throughout the region, along with high elevation snowfall. Any precipitation amounts are expected to be seen as beneficial, with the strong wind potential on Saturday prompting Wind Advisories across southern Nevada. Snell Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php $$