118 FXUS01 KWBC 160806 PMDSPD Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 400 AM EDT Tue Jun 16 2026 Valid 12Z Tue Jun 16 2026 - 12Z Thu Jun 18 2026 ...Significant heavy rainfall expected from South Texas to the lower Mississippi Valley through the next couple of days... ...An outbreak of severe weather from the Midwest to the lower Great Lakes/Ohio Valley is forecast on Wednesday... ...Not as hot on the West Coast... A weather pattern favoring cold air intrusions from Canada is bringing a cool and dry airmass into much of the eastern two-thirds of the country. This weather pattern will also send a couple of quick-moving low pressure systems across the Northern Tier, bringing showers and embedded thunderstorms with gusty winds through the next couple of days. The first system will move across the Great Lakes today and tonight. The second system is forecast to be the stronger of the two, and will rapidly intensify over the Northern Plains Wednesday morning. An outbreak of severe weather is forecast to emerge across Iowa to Illinois Wednesday morning ahead of a warm front. Additional severe thunderstorms are forecast to erupt through Wednesday night across the remainder of the Midwest, the lower Great Lakes and toward the Ohio Valley as the low pressure system intensifies further and forces its way eastward. The Storm Prediction Center has highlighted an enhanced to moderate risk of severe thunderstorms across the Midwest on Wednesday. Large hail, damaging winds, and tornadoes are possible with these severe storms. In addition, the Weather Prediction Center is highlighting a slight risk of flash flooding in this general area on Wednesday. By Thursday morning, the strong low pressure system with bring very gusty winds across the Great Lakes as the threat of severe weather reaches upstate New York and down along the Ohio River ahead of the trailing cold front. While the cool air mass dominates the weather pattern across much of the central and eastern U.S., a prolonged heavy rainfall event continues to take shape across South Texas through the Lower Mississippi Valley. This is in response to complex interactions among a low- to mid-level disturbance exiting the Mexican plateau, tropical moisture near the western Gulf and northeastern Mexico, and the same cold front becoming nearly stationary just inland from the Gulf Coast. Through the next three days, storm total rainfall of 5-7" with locally higher amounts can be expected along the Texas coastline into Louisiana. Numerous instances can be expected through Thursday morning in this area, some of which could be significant. In addition, the National Hurricane Center continues to monitor the potential for tropical cyclone development near the Texas Gulf Coast over the next couple of days. Enhanced tropical rainfall could be moving up the Texas coast on Wednesday, reaching into Louisiana by Thursday morning. Along the West Coast, heat advisories remain in effect today for portions of the area before temperatures cool off some more on Wednesday. The Desert Southwest and the Central Valley of California will remain hot, with highs in the 110s and 90s-100s, respectively. Florida will see more numerous showers and thunderstorms across the northern part of the state over the next couple of days. Kong Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php $$