Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 353 PM EDT Sat Jul 25 2020 Valid 00Z Sun Jul 26 2020 - 00Z Tue Jul 28 2020 ...Hurricane Hanna to make landfall in south Texas later today with torrential rainfall, strong winds, coastal flooding, and severe storms expected... ...Heavy Rainfall/flash flooding possible for parts of the Southwest, Rockies, and the Northern and Central Plains over the next few days... ...Cooling trend in the Plains, becoming hotter in the Northwest, staying hot in the Northeast... Hurricane Hanna is knocking on south Texas's door and will make landfall later this afternoon. Strong winds and heavy rain -- with intense rainfall rates of 2-3" an hour at times -- will accompany the storm along and near its path tonight and into early Monday. Copious amounts of rainfall, with local amounts up to 18", will result in both flash flooding and river flooding that could become life threatening from the southern Texas coast to the Lower Rio Grande Valley. The concern for such dangerous flooding in South Texas due to Hanna has led to the issuance of a rare High Risk for excessive rainfall Saturday into Sunday morning. The heavy rain and flash flood threat extends as far north as southeast Texas and southern Louisiana as rain bands associated with Hanna track overhead this evening. In addition, tropical storm force winds will lead to some power outages and tree damage while coastal areas along Hanna's path brace for potentially damaging storm surge and coastal flooding. A slight risk of severe thunderstorms also exists along and just north of where Hanna is forecast to make landfall. For more information on Hanna's status and expected track, see advisories from the National Hurricane Center. Elsewhere, areas of locally heavy rainfall are likely this weekend into Monday across portions of the Four Corners region and the Nation's Heartland. Monsoonal moisture has set the stage for bouts of heavy rainfall over the Southern Rockies (Slight Risk of excessive rainfall) before the risk of heavy/excessive rainfall shifts east farther into the southern High Plains. Rainfall rates may be heavy at times, particularly in the afternoon and evening hours. To the north, a Canadian low pressure system forces a cold front into the Plains which combined with the aforementioned monsoonal moisture should generate organized and potentially severe thunderstorms into the start of the week. A slight risk for flash flooding is forecast from the central High Plains to the Upper Mississippi Valley to the Midwest Sunday into Sunday night (Moderate risk in South Texas due to Hanna), and portions of the Southern and Central Plains Monday (Slight risk). The cold front sweeping across the central U.S. ushers in cooler and more comfortable conditions across the northern Rockies and Great Plains Sunday. By Monday, the surge of cooler temperatures reaches the central Plains and south-central Rockies. After a cool start to the weekend, temperatures rebound to above normal leves across the Northwest Sunday and Monday with high temps making a run at the century mark in spots. To the East, hot and humid conditions extend across much of the eastern third of the Lower 48 with heat indices in the Northeast reaching as high as 100 degrees both Sunday and Monday afternoons. Mullinax Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php