222 FXUS01 KWBC 160823 PMDSPD Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 400 AM EDT Thu Jul 16 2026 Valid 12Z Thu Jul 16 2026 - 12Z Sat Jul 18 2026 ...Additional excessive rainfall likely across the Texas Hill Country today, with focus shifting toward the Big Bend on Friday... ...Anomalous heat and humidity persisting across the Northern Plains/Upper Midwest while spreading into the northern Mid-Atlantic... ...Air quality alert from the upper Midwest through the Great Lakes into the Northeast... ...Monsoonal showers and thunderstorms persist across the interior western U.S with greatest flash flooding threat near the southern borders of Arizona and New Mexico... ...Severe thunderstorms for portions of western Montana later today; strong thunderstorms possible for northern New England today... As the anomalous upper high prolongs a heatwave across the northern states, a slow-moving weather regime continues to transpire across the southern tier states where a front remains stationary. An upper-level low has migrated westward into the southern High Plains to support a renewed round of heavy thunderstorms across the Texas Hill Country early this morning. Continued influx of Gulf moisture is forecast to interact with the upper low to bring additional rainfall amounts of 6-8" with locally 10+ inches today as these heavy thunderstorm clusters generally track northward from the Texas Hill Country through central Texas. This will likely exacerbate the ongoing flash flooding situation in the region. By Friday, the focus of the heavy rainfall is forecast shift west toward the Big Bend area, and possibly be confined to western Texas by Saturday morning. Meanwhile, more heat and humidity is expected for the Northern Plains and Great Lakes with daily maximums holding steady in the 90s to lower 100s for the next few days. Cooler air will penetrate deeper into New England today under gusty westerly winds behind a cold front followed by a reinforcing shot of cooler air by Friday morning with the passage of a second cold front. Unfortunately, the influx of cooler air will also bring smoke from Canadian wildfires into the northeastern quarter of the country. Meanwhile, another day of triple-digit high temperatures and elevated humidity is expected for the northern Mid-Atlantic before readings drop slightly into the 90s on Friday. Some strong thunderstorms are possible later today across northern New England prior to the arrival of the second cold front. In the western U.S., severe thunderstorms are possible later today across western Montana on the backside of a low pressure wave near the western end of the front. Meanwhile, monsoonal thunderstorms are forecast to track from north to south across the Four Corners region today under the influence of the upper low over the southern High Plains. The greatest flash flooding threat is expected to be near the southern borders of Arizona and New Mexico for the next couple of days. More monsoonal showers and thunderstorms will develop across the Intermountain West into the eastern portion of the Great Basin. Scattered thunderstorms will be lifting farther north into the Mid-Mississippi and Ohio Valleys later today as the stationary front gradually dissipates. The frontal wave over the northern High Plains will reach the central Great Lakes by Saturday morning. Scattered strong thunderstorms can be expected mainly across the upper Great Lakes on Friday, shifting to the lower Great Lakes by Saturday morning as the frontal wave moves eastward. Kong Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php $$