Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 412 PM EDT Thu Jul 22 2021 Valid 00Z Fri Jul 23 2021 - 00Z Sun Jul 25 2021 ...Heavy rainfall and the threat for flash flooding continue across the Southwest as Monsoon activity remains high... ...Midsummer heat persists across the Northern/Central Plains and spreads into the Midwest, with the threat of severe thunderstorms on Friday... ...Elevated to critical fire weather concerns remain throughout the Northern Rockies and Great Basin... Heavy rainfall and the threat for flash flooding from daily storms associated with the Southwest Monsoon will continue through the short-term forecast period, with Friday of particular concern. An upper-level ridge centered over the Four Corners region and an upper-level low retrograding westward out of Texas are funneling an anomalously high amount of moisture into the region. A Slight Risk (level 2/4) of Excessive Rainfall remains in effect through tomorrow morning for portions of Arizona, western New Mexico, southwest Colorado, and southern Utah for the threat of heavy downpours with rain rates of 1 inch per hour possible. On Friday, a Moderate Risk (level 3/4) is in effect for portions of central and southeastern Arizona, with a broader slight risk in effect for additional portions of Arizona, New Mexico, and into central Colorado. The Moderate Risk area is highlighted for the threat of up to 2 inches per hour rain rates and widespread rainfall totals of 1 to 3 inches. A Slight Risk is also in effect for portions of central and southeastern Arizona and southwestern New Mexico on Saturday for the threat of an additional 1 to 2 inches of rain. Various Flash Flood Watches are in effect across the region, with most of Arizona under a watch through at least Saturday evening. The intense rainfall over burn scars remains a concern for flash flooding and the potential for debris flow. Flash flooding will also be a threat locally for areas that have already seen heavy rainfall over the past few days as the Monsoon storms have ramped up. Hot weather will continue into the beginning of the weekend throughout the Northern and Central Plains, as well as parts of the Midwest. High temperatures generally in the mid- to upper 90s are expected across the region, with little relief at night as temperatures remain in the low to mid-70s. In addition to the heat, moisture will increase ahead of a cold front moving east across the Northern Plains and Upper Midwest on Friday leading to the chance of thunderstorms, some of which may be severe. The Storm Prediction Center (SPC) has issued a Slight Risk (level 2/5) for severe weather for central and eastern North Dakota and northern Minnesota, with damaging winds and hail the main threats. Farther west, gusty winds and low humidity combined with the established dry terrain will lead to yet another day of fire weather concerns Friday. The SPC has highlighted portions of northeastern Montana for Critical fire weather conditions and most of the rest of Montana and southern Idaho for Elevated fire weather conditions. Elsewhere, high temperatures will begin to increase into the low to mid-90s from the Gulf Coast north through the Missouri, Mississippi, and Ohio Valleys as the upper-level ridge begins to build further to the east. Excessive heat will begin to become more of a concern where these higher temperatures are combined with high humidity. Heat advisories are in effect for portions of the Gulf Coast from the New Orleans area east to the central Florida Panhandle and the Tampa area as heat indices may climb into the upper 100s on Friday. An Excessive Heat Watch will also take effect Friday afternoon for the Kansas City area where heat indices over 100 are expected into the weekend. Thunderstorm chances will increase for the Midwest as a warm front lifts north through the region on Friday and Saturday. Thunderstorm chances also look to increase for the Florida Peninsula as a trough of low pressure becomes established across the area. Putnam/Snell Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php