Area Forecast Discussion
Issued by NWS Quad Cities, IA IL

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483 FXUS63 KDVN 241906 AFDDVN Area Forecast Discussion National Weather Service Quad Cities IA IL 206 PM CDT Mon Jun 24 2024 .KEY MESSAGES... - Active next 36 hours with thunderstorms, some strong to severe and heavy rain expected. - Actual evolution of storms and timing is uncertain and falls into 3 different scenarios explained below. - Quiet conditions expected Wednesday and Thursday before another round of storms moves in for Friday and Saturday && .SHORT TERM /THROUGH TUESDAY NIGHT/...
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Issued at 1236 PM CDT Mon Jun 24 2024 Active period expected as hot and humid air will serve as the energy for strong to severe thunderstorms through the short term. A couple different scenarios are possible with the storms in the next 6 to 30 hours. Questions about storm mode and evolution and thus threats abound at the time of this issuance, however a few things are known. First, there is a warm front draped from Bismarck, ND southeast to Dubuque. Also, the largescale flow is curved back to the SE and into our area as well. These two knowns suggest that convection to our north in the next 6 to 30 hours will dive south and into our area. The better chance for severe storms will likely be in the next 6 to 24 hours, before we transition to more of a flash flood threat. Scenario 1: A MCV across Minnesota is expected to continue moving southeast towards the the CWA this afternoon into the early evening. Storms could redeveloped near this MCV. With an extremely unstable warm sector, and deep layer shear of 30 to 40kts storms should continue to build. If they do redevelop, expect storms to become cold pool dominant as a severe MCS barrels south towards us in the early evening. With current environment, would not be surprised to see widespread 70 MPH gusts with some embedded higher gusts. This one is the least likely to occur, however if it does, it will likely lead to the most severe weather. Scenario 2: Thunderstorms redevelop this afternoon across western MN. Supercells initially will turn into a MCSs with a strong cold pool. This system will track south and east towards our area later this evening and into the overnight. How far west this activity is will be tied to the left over cloud cover over MN and the CAP to our SW. Do believe that this system will track further SW and more into our CWA if this occurs. This would bring severe winds to the area later in the overnight. As these storms move out of the area, some OFBs would be left. Storms would redevelop then in the late afternoon and into the evening on Tuesday. While initial storms could lead to severe winds, this will turn quickly into a slow moving storm environment and flash flooding will be likely. Scenario 3: No storms develop until Tuesday. While this seems to be the less likely solution, it is still plausible. In this case, a cold front tied to convection across WI and eastern IL, will stall across the area. Daytime heating, along with the boundary will lead to showers and storms forming. Deep layer shear is lower, so strong to severe storms will be short lived before transitioning to a heavy rain and flash flooding threat. Right now, this threat is maximized along and south of I80. That could change though. Regardless of what happens, we expect impactful weather through the next 36 hours. As far as heat goes, with thunderstorm potential through the period, high temperature forecast will be tricky. Tomorrow has a high bust potential. As such, will hold off on any heat advisory at this time.
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&& .LONG TERM /WEDNESDAY THROUGH SUNDAY/...
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Issued at 206 PM CDT Mon Jun 24 2024 Active pattern is expected to continue through the rest of the long term. While there appears to be a break in showers and storms Wednesday and Thursday,it does not look like a completely dry forecast. We remain aligned in the track for ridge riders. Any of these could produce showers and storms. Late in the week, another more robust system is expected to affect the area. This will bring what appears to be a MCS into the area Friday morning. While there could be strong to severe storms, what does seem more likely is the chance for heavy rain. This will just add to the flooding across the area.
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&& .AVIATION /12Z TAFS THROUGH 12Z TUESDAY/... Issued at 1236 PM CDT Mon Jun 24 2024 Expect VFR conditions to be the main flight category through the period. There are chances for thunderstorms through the period, however timing and confidence is very low. Expect amendments later in the period as timing in storms increases. These storms could bring IFR vsbys and strong gusty winds of close to 50kts. && .HYDROLOGY... Issued at 929 PM CDT Sun Jun 23 2024 No significant changes for the Cedar River basin this evening with the new forecasts. The rise on the Cedar River at Cedar Rapids has been slowed some and still may reach 14 ft or Moderate flood stage early Friday. For the Mississippi, flood watches have been converted to flood warnings for Dubuque Lock and Dam, Camanche, and Rock Island Lock and Dam sites this evening. Additional warnings can be expected in the coming days. .Previous Discussion. The Mississippi River is expected to reach flood stage at multiple locations, including the Rock Island gage, by the middle of this week. Long term we expect the Mississippi to reach Moderate and/or Major flood stages the week of the Fourth of July, with the crest at the Rock Island gage possibly reaching just over 18 feet early on the Fourth of July. However, a larger margin of error should be taken into consideration when forecasting precipitation amounts and locations in the 7-10 day timescale. Watches are currently out for most of the Mississippi River and warnings will follow in the next few as a clearer picture is drawn on what precipitation and routed water we have coming downstream. In the latest forecast package, we have opted to upgrade Gladstone and Burlington to a River Flood Warning, aided by the recent rainfall north of the area. The Rock River is also expected to reach flood stage in Joslin, with an increase noted into Action Stage at Moline. A River Flood Warning has been issued for Joslin in this latest forecast package, which is forecast to hit flood stage tomorrow afternoon. We will continue to see additional rainfall through this coming week, which may lead to further fluctuations in the river levels. If heavy rainfall is seen, then increases can be expected. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...None. IL...None. MO...None. && $$ SHORT TERM...Gibbs LONG TERM...Gibbs AVIATION...Gibbs HYDROLOGY...Gross