


Area Forecast Discussion
Issued by NWS Quad Cities, IA IL
Issued by NWS Quad Cities, IA IL
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514 FXUS63 KDVN 100844 AFDDVN Area Forecast Discussion National Weather Service Quad Cities IA IL 344 AM CDT Thu Jul 10 2025 .KEY MESSAGES... - There is a daily risk of showers and thunderstorms through Saturday. As for severe weather, there is a Marginal Risk for portions of the local area today and tonight, and a Slight Risk for Friday. - There is a signal suggesting a risk of heavy rainfall with any of this thunderstorm activity, which may compound on itself and lead to flooding, both flash and river. With several rivers already running above normal for mid summer, the risk of river flooding would increase if the heavy rainfall is realized. - Seasonal temperatures and humidity levels will continue into next week. && .SHORT TERM /THROUGH TONIGHT/... Issued at 330 AM CDT Thu Jul 10 2025 Today...A MCV type feature was evident on water vapor imagery and even regional RADAR loops rolling out of southeast SD into southwest MN and northwest IA ATTM. Upstream linear MCS acrs western IA will look to propagate eastward into the CWA this morning through midday, assisted by the MCV and some cold pool kinematics. There may be some isolated WAA wing elevated cells out ahead of the main system, but extrapolate the main convective line into the western/northwestern CWA after 7-8 AM, with decaying remnants and outflow reaching the MS RVR by noon. These times may be rough, as also see the potential of decaying remnants flaring up in the late morning into early afternoon heating and MCV lift/shear to strong or even severe storm cells acrs the MS RVR vicinity and moving acrs west/northwest IL during the afternoon. Besides the threat of all type of severe including a tornado on a boundary, A PWAT feed of 1.5 to 1.8 inches will fuel locally heavy rainfall. Away from the MCV enhanced shear, the ambient shear and vertical wind flow rather weak but may allow for slower storms and higher residence times for very localized flooding. High temps, DPTs and resultant SBCAPE/instability build up again a challenge depending on the incoming MCS and convective debris to deal with or erode. But not much of or any EML indicated on the fcst soundings for today, and convective temps progged to be in the mid to upper 80s. Many scenarios possible. Tonight...After a potential convective lull during the late afternoon into early evening(if earlier day storms are more vigorous and don`t decay too early), another more subtle upper wave seen on the WV imagery currently acrs southeast MT/far northeast WY will look too roll acrs the area tonight. And with the models suggesting a renewed southwesterly 25+ KT LLJ streaking up acrs the area and impinging on lingering outflow boundaries, a main quasi-stationary front or other thermal descrepancies, more storms should take off tonight possibly developing overhead and/or just off to the west and will move in later in the evening and overnight. Again, they will pop earlier in the evening or late afternoon if the convection coming in this morning just fades and doesn`t re-flare up. SREF placement has this activity more likley occurring along and north of the I-80 corridor, with rounds of convection lasting into early Friday morning. Effective shear profiles not the strongest tonight even with another wave aloft(25-30 KTs), but with ongoing CAPE/THTA-e feed still see a potential damaging wind threat, and a tornado on a lingering boundary with low LCL`s in place. Of more of a widespread concern will be the potential for training heavy rain producing storms and eventual flash flooding this set-up could produce. Still a lot of uncertainty on this storm axis placement and maintenance/back-building potential and will hold of a Flood Watch for now, but later shifts may have to consider one if the same area looks to be indicated by the models and frontal placement lay out after today`s convective activity. && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... Issued at 330 AM CDT Thu Jul 10 2025 Friday...Much of what occurs Thu night and lingers into Friday will effect the convective scenario this day. But the most likely scenario will be that as a more substantial upstream short wave pushes acrs the MO RVR Valley, a high CAPE air mass of 3000-4000 J/kg in place locally if we get the heating and convective debris decays fast enough, will be enough for effective shear profiles of 30-40 KTs for more strong to severe storm development Friday afternoon and evening both locally and off to the southwest toward northeast KS. Waves of strong to severe convection in clusters or MCS form will move acrs the region into early Sat morning, again with all modes of severe possible but large hail will have a melting battle reaching the sfc. With a high Sigma, model indicated PWAT feed of 2 to 2.3 inches, again flash flooding and areal flooding becoming a concern where storms move acrs repeatedly/train...especially acrs areas that get hit hard today(Thursday). Definitely a messy fcst period with many parameters to take into account. Saturday through Wednesday...With the main short wave progression, hopefully Sat storm chances will set up along and east of the local area that will probably need a break in the action by that time. Both sfc and upper ridging look on tap for a mainly dry and seasonable Sunday into Monday, before precip chances start to increase again toward mid next week. && .AVIATION /06Z TAFS THROUGH 06Z FRIDAY/... Issued at 1257 AM CDT Thu Jul 10 2025 Besides the chance for some patchy fog developing(not as much as last night), and an isolated elevated shower or thunderstorm developing out of the ACCAS wing in elevated warm air advection acrs the area, generally a VFR fcst into Thu morning. Then will have to watch how the remnants of the upstream MCS do as it approaches from the west, if they continue to decay or re- intensify by late morning into midday heating. Then there will be lingering boundaries and convective debris for more storms to fire on later this afternoon and tonight as the southwesterly LLJ starts to increase again converging up and over these features. This makes for a challenging TAF fcst trying to time convective windows, with on and off chances for most of the period after 14z. PROB30`s will have to be used until better defined storm windows become evident. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...None. IL...None. MO...None. && $$ SHORT TERM...12 LONG TERM...12 AVIATION...12