517 FXUS63 KDVN 051834 AFDDVN Area Forecast Discussion National Weather Service Quad Cities IA IL 134 PM CDT Fri Jun 5 2026 .KEY MESSAGES... - There is a Slight Risk (Level 2 out of 5) for both severe weather and heavy rainfall tonight across the entire area with a more favored area south of Interstate 80. - After possible scattered storms Saturday and Saturday night, another round of widespread showers and thunderstorms is likely Sunday night into Monday night that could produce heavy rainfall. - Hot and humid conditions are forecast to develop for the second half of next week with the potential for high temperatures in the lower to mid 90s Wednesday through Friday. && .SHORT TERM /THROUGH MONDAY NIGHT/... Issued at 132 PM CDT Fri Jun 5 2026 What a difference a day makes! A humid air mass has spread into our entire area, and with that, our local region saw it's first notable rain in many weeks. Our north and western counties saw 1 to 3 inches of rain overnight into this morning, with the highest totals in the far north central areas. Dew point values have reached 70 throughout the entire CWA. The diffuse front which lifted into the area remains from our northeast counties on west southwest to near Newton, Iowa on west to near Omaha NE. Looking aloft, scattered storms are moving east over the upper Midwest over MN and northeast NE. These are associated with the next short wave in the zonal flow aloft, and this wave should begin to bring lift to our western counties around 6 PM. Tonight, models are widely varied on placement of new storms, but generally, looking at the wave aloft, it appears that the veered 850mb moisture transport currently aimed to southern MI will back to the south over the Midwest, and reload that elevated thunderstorm potential into Iowa along and north of the front as the night progresses. The flow aloft is not overly fast, around 30 kts. Thus, propagation of storms may take quite a while overnight to reach our counties. More likely, the storms will zipper eastward along the front as the night progresses, with strong to lower end severe storms reaching into our I-80 corridor and south counties by 9pm to Midnight. Overnight, some movement east is expected, but this again is not a quick movement. While CAPE and DCAPE support some strong wind gusts and marginally severe hail, the mid level lapse rates are much weaker over the central and east portion of the CWA, as the steepest mid level remain over southwest Iowa and Nebraska. PWAT values on our 18Z sounding are 1.64" and this air mass already produced a swath of heavy rainfall in our north. I expect much of the same tonight, and into the weekend with this air mass and pattern, which could eventually lead to flooding if it impacts areas multiple times. For now, rainfall tonight in our central and south look to be 0.5 to 1.5 with some swaths of 2+, falling on mainly D-0 counties that need rain. I'm opting to not issue a flood watch given these dry antecedent conditions. Looking through Saturday and Saturday night, this boundary is expected to remain in the area, with little synoptic predictable lift. However, advection over the front, with inevitable mesoscale features supporting new storm development will drive some scattered storms, each of which will bring heavy rain, frequent lightning, and low end severe risk through Saturday night. Sunday morning to Monday, this chaotic pattern will slowly begin to be influenced by a broad upper low lifting northward from the southern Plains. This will lead to an extended period of pops and rain/thunder potential, with a high PWAT air mass in play. While QPF placement is uncertain, as is timing of any period but this is a wet pattern in general, with frequent chances for rainfall that could be heavy at times. && .LONG TERM /TUESDAY THROUGH THURSDAY/... Issued at 132 PM CDT Fri Jun 5 2026 Tuesday onward, an Omega Block redevelops across the CONUS as 500 MB ridging builds back into the Central Plains while a closed low sits off of the East Coast and another in the Northern Rockies. High pressure is sprawling across the southern US with the Gulf open to pull moisture northward and into the area. This will allow dewpoints and temperatures to quickly climb Tuesday through Friday with high temperatures potentially into the mid 90s Wednesday through Thursday. No matter the specific values, it looks like the second half of next week will be hot and humid across the area. && .AVIATION /18Z TAFS THROUGH 18Z SATURDAY/... Issued at 1223 PM CDT Fri Jun 5 2026 A stationary boundary remains over our area, generally near I-80 from west to east. With moisture converging along this boundary, widespread rain showers and some thunder have persisted well into the late morning hours and could continue to be drizzle and rain showers early this afternoon north of Highway 34. Some isolated storms remain possible, but the next round of more notable thunderstorm activity should arrive late this evening as a wave moves along the front from west to east. These storms will be similar to last night, offering heavy rain and low cigs/visibilities and some threat for gusty winds. While the best 60-80% chance for storms will be along and south of I-80 tonight, storms are possible (30%) even in the northern areas like DBQ. Rain showers and lower cigs may linger into Saturday morning once again before gradually improving aviation develops, very chaotic, but also quite similar to today. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...None. IL...None. MO...None. && $$ SHORT TERM...Ervin LONG TERM...Cousins/Ervin AVIATION...Ervin