


Area Forecast Discussion
Issued by NWS Quad Cities, IA IL
Issued by NWS Quad Cities, IA IL
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780 FXUS63 KDVN 111828 AFDDVN Area Forecast Discussion National Weather Service Quad Cities IA IL 128 PM CDT Fri Jul 11 2025 .KEY MESSAGES... - An Enhanced Risk (Level 3 of 5) of severe weather is expected this afternoon into tonight. Damaging winds are the primary hazard. A few tornadoes and large hail can not be ruled out. - Flash flooding is likely for portions of the area, especially for those that have received 2 to 4 inches of rainfall within the last 24 hours. Rainfall rates of 2 to 4 inches per hour are expected. Additional rainfall amounts between 1 to 3 inches are possible. - Quieter weather arrives this weekend with only isolated thunderstorms. Temperatures begin to increase next week ahead of our next weather system by the middle of the week. Increasing thunderstorm chances are expected with this next system. && .SHORT TERM /THROUGH TONIGHT/... Issued at 126 PM CDT Fri Jul 11 2025 Several locations across the area received 2 to 4 inches of rainfall over the last 24 hours. This will contribute greatly to the expected hazards through tonight. In the meantime, a decaying area of showers and thunderstorms continues to lift northeastward out of our region. A positively-tilted shortwave trough is situated over the central Great Plains and is expected to progress eastward through this afternoon and evening. Late this morning and early this afternoon, pockets of sunshine allow for rapid daytime heating and destabilization. Temperatures reach the middle to upper 80s along and south of Interstate 80, with upper 70s and lower 80s to the north where clouds linger. This sets the stage for a very active afternoon and evening. With the approaching trough and afternoon destabilization, thunderstorm development is expected near convective outflow from morning thunderstorms across our north and ahead of the approaching trough to our west. These thunderstorms are forecast to develop in a favorable environment for severe weather and flash flooding. As such, the Storm Prediction Center has upgraded to an Enhanced Risk (Level 3 of 5) over the area. Convectively-enhanced low-level winds support curved hodographs that favor supercell development initially. These supercells will pose an all hazards threat, with damaging winds, marginally large hail, and even a few tornadoes possible. Flash flooding will be another hazard. Low-level winds favor continuous moisture transport from the southwest into our area, alongside an already deep-saturated airmass. Given weak and backed upper-level winds, high-precipation rates are expected. 2 to 4 inch per hour rainfall rates are probable. As the afternoon and evening progresses, additional thunderstorm development and gradual upscale growth into lines of thunderstorms is anticipated. This upscale growth will transition the hazards to a primary threat of damaging winds and flash flooding as cold pools congeal. With that said, a couple tornadoes can not be ruled out. Slow movement and training of thunderstorms appears likely. Weaker upper-level winds and shear vectors generally in the same direction as thunderstorm orientation supports prolonged heavy rainfall. With this expectation, widespread additional rainfall of 1 to 3 inches is forecast with locally higher amounts possible. A Flood Watch is in effect for much of the area as a result due to this threat of flash flooding and river flooding. Late tonight and into early Saturday morning, thunderstorms gradually shift eastward, along with the trough and precipitation tapers off by midnight with any lingering showers and thunderstorms dissipating after midnight. Patchy fog may develop behind this rainfall with plentiful moisture and cooler temperatures filling in behind this activity. Temperatures cool into the upper 60s by Saturday morning as remnant clouds continue to linger. && .LONG TERM /SATURDAY THROUGH THURSDAY/... Issued at 126 PM CDT Fri Jul 11 2025 With widespread cloud cover and rain-cooled air lingering Saturday morning, comparatively quieter weather is anticipated for Saturday. With that said, at least a few afternoon thunderstorms can be expected during the mid-afternoon before everything clears to the east by evening. Temperatures reach the middle 80s across the area on Saturday. Cooler temperatures continue on Sunday, with morning temperatures down into the lower 60s and afternoon temperatues reaching the middle 80s once again. Mostly sunny skies offer up beautiful weather to end the weekend. Temperatures climb back into the upper 80s and lower 90s to start the week under mostly sunny skies and ahead of our next system. Heading towards the middle of the week, our next weather system brings increasing thunderstorm chances and cooling temperatures. A cold front could bring upper 70s and lower 80s to the area late in the week. && .AVIATION /18Z TAFS THROUGH 18Z SATURDAY/... Issued at 1212 PM CDT Fri Jul 11 2025 VFR conditions and southeast winds are expected during the early afternoon. A few showers and thunderstorms have developed near and north of CID and DBQ. Brief aviation impacts and VCTS are possible through early afternoon. As the afternoon progresses, thunderstorm development is expected near western terminals initially. Scattered thunderstorms may proceed a stronger line of thunderstorms that moves east across the region this afternoon and evening. Gusty and variable winds are expected with these thunderstorms. MVFR visibility and ceilings are likely with thunderstorms with reductions to IFR ceilings and visibility possible at times. Behind these thunderstorms late this evening, rain may linger along with MVFR ceilings. Fog is expected to develop across the area once rain ends with MVFR visibility with MVFR or IFR ceilings after midnight. Eventual clearing will arrive towards the end of the TAF period. && .HYDROLOGY... Issued at 107 PM CDT Fri Jul 11 2025 What is NEW... Flood watches have been issued for the Wapsipinicon River near DeWitt and for the Mississippi River from Gladstone, IL (L/D 18) to Burlington, IA. Discussion... Bands of heavy rain fell across eastern Iowa and northwest and west central Illinois. Rainfall ranged from 1 to 4 inches with 3-4+ inches in the bands of heavier rainfall. The urban areas of Dubuque and the Quad Cities were hit hard with heavy rainfall last night and are especially at risk for flooding. Most of the area is abnormally dry or in moderate drought and transpiration from agricultural fields is near maximum. As of right now river gages are showing little to no increases suggesting a good chunk of last nights rainfall appears to have soaked into the ground. However, another round of heavy rainfall is expected late this afternoon through sunrise Saturday. Early estimates suggest another 1 to 3 inches of rain occurring with pockets of 3+ inches possible due to PWATs above the 90th percentile. If the heavier bands of rain occur in roughly the same areas as last night, then considerable runoff will occur due to soils being near saturation. If the heavier rain occurs in areas that received less rainfall last night, then a good portion of the rain may soak into the ground. Regardless of which scenario occurs, baseline ground water flow will increase and eventually reach area waterways. As a result, area rivers are forecast to see general within bank rises over next next 5-7 days. If the upcoming round of heavy rain occurs in areas that have saturated soils, then portions of some rivers may reach flood stage. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...Flood Watch until 1 AM CDT Saturday for IAZ040>042-051>054- 063>068-076>078-087>089-098-099. IL...Flood Watch until 1 AM CDT Saturday for ILZ001-002-007-009- 015>018-024>026. MO...None. && $$ SHORT TERM...NWS LONG TERM...NWS AVIATION...NWS HYDROLOGY...08