Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 405 PM EDT Wed Jul 14 2021 Valid 00Z Thu Jul 15 2021 - 00Z Sat Jul 17 2021 ...Heavy rain and potential flooding for parts of the Central U.S. and the Desert Southwest... ...Heat wave across the western U.S. abates through the end of the week; some additional hot temperatures possible beginning this weekend... ...Severe weather possible today over portions of the upper Midwest, and New England... The active summertime pattern of mainly afternoon/evening intense thunderstorms with heavy downpours will continue to make weather headlines through the middle of the week. This especially holds true for portions of the Upper Midwest, Central Plains, the Desert Southwest, and the Florida Peninsula. Through next week, a sprawling slow moving cold front currently positioned from northern Colorado into Quebec will meander southward, sparking thunderstorm development along the way each day. The front combined with several areas of enhanced lift aloft will support storms with high rainfall rates over the Upper Mississippi Valley today, where a Slight Risk of excessive rainfall remains until tomorrow morning. In addition to the heavy rain threat today, an Enhanced Risk of severe weather extends from North-Central Iowa into West-Central Wisconsin through early tomorrow, per the Storm Prediction Center. Damaging winds are anticipated to be the primary threat over this area, although large hail and tornadoes are also possible. Over the Desert Southwest, monsoon season is in full swing, and the upcoming week is expected to be no different. As rich monsoon moisture wraps into the region, afternoon and evening showers are expected to remain across the Four Corners each day, especially in southern Arizona and western New Mexico. Given relatively weak steering winds aloft, many of these storms will likely be slow moving and result in flash floods for canyons, burn scars, and other vulnerable areas. A Slight Risk for excessive rainfall is in effect over Central Arizona and far western New Mexico today, and Southeast Arizona/Southwest New Mexico tomorrow. In the temperature department, the ongoing heat wave across much of the western U.S. is abating across the Southwest as monsoonal moisture increases, but noteworthy positive anomalies will still exist across interior portions of the Pacific Northwest and Great Basin through Thursday. Overnight low temperatures are expected to be above normal as well and across a greater portion of the western U.S. compared to the daytime highs. Unfortunately, the return of triple digit highs are a distinct possibility over Central Montana beginning Saturday, before spreading into Idaho later this weekend as high pressure builds over the region. Accordingly, an Excessive Heat Watch is in effect beginning from Saturday through Wednesday evening. Elsewhere, warm and humid conditions will persist across much of the Eastern U.S. through the end of the week before cooler weather arrives in time by Saturday. Asherman/Hamrick Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php