534 FXUS63 KDVN 101916 AFDDVN Area Forecast Discussion National Weather Service Quad Cities IA IL 216 PM CDT Wed Oct 10 2018 ...HYDROLOGY UPDATE... .SYNOPSIS... Issued at 400 AM CDT Wed Oct 10 2018 As of 2 AM, a surface low was located over central and north central Iowa with a trailing cold front extending SW into NW MO. A band of moderate to heavy rain showers was streaming NNE from NE MO along the MS River Valley. As of 230 AM, KDVN has picked up about 0.80 inches in the past 90 minutes. Temperatures were in the upper 60s to lower 70s, with dew points in the mid and upper 60s. && .SHORT TERM...(Today and Tonight) ISSUED AT 400 AM CDT Wed Oct 10 2018 The low will lift NE into central WI today, dragging the cold front through the area from west to east from mid morning to mid afternoon. Some CAMs show the current slug of precipitation lifting north of the area this morning with some scattered convection developing along the actual cold front as it moves eastward through the area later this morning and into the the afternoon. The SPC has a Marginal Risk area east and southeast of a line from Dubuque to Muscatine for an isolated severe storm producing a damaging wind gust. Heavy rainfall will still be possible along and east of a line from Dubuque, to Keosauqua, and south to Memphis, MO through early afternoon as rain continues to stream across these areas. Thus the the Flash Flood Watch will remain in effect for these areas. We did trim off some west and northwestern counties as there is no longer a flash flood threat there. Rain should end from west to east from 9 AM to about 3 PM. Temperatures will fall through the afternoon with readings by the evening commute in the upper 40s west to low to mid 60s east. Strong west winds will surge in behind the front with some gusts of 25 to 30 MPH at times. .LONG TERM...(Thursday through Tuesday) ISSUED AT 400 AM CDT Wed Oct 10 2018 The extended is characterized by NW flow, clipper type systems every other day followed by a cool down a some am frost potential. Tonight gusty NW wind will continue as the low moves into the upper Great Lakes. With lingering cloud cover and the wind, lows Thu morning will be in the mid and upper 30s, and frost shouldn't be an issue. Highs Thu will only be in the mid 40s to low 50s with continued brisk NW winds. High pressure brings some partial clearing and light winds Thu night and Fri morning, with lows in the low to mid 30s. Frost is possible especially north of I 80. Highs Fri will be in the mid and upper 40s. Models have come into better agreement now with a low chance rain period skirting the southern half Friday. Light amounts are expected. Frost is again possible mainly NE early Sat, with lows in the 30s. A clipper type system and southern disturbance then bring some slight/low chc Pops for Sat night and Sun. Another frosty morning is possible early Monday with lows in the 30s. Tue into Wed yet another clipper possible with low chc Pops. && .AVIATION...(For the 18Z TAFS through 18Z Thursday Afternoon) ISSUED AT 1238 PM CDT Wed Oct 10 2018 After a fine line of showers along a frontal system pushes east of DBQ and MLI early this afternoon, expect mainly MVFR CIGs of stratocu, with a few areas possibly rising toward VFR levels southwest of I80. SFC winds will continue to veer southwest to west with the frontal passage later this afternoon and evening, and become gusty overnight in tightening pressure gradient. MVFR CIGs may linger tonight into early Thu morning at all sites except maybe BRL, but should rise to VFR levels by late Thu morning. ..12.. && .HYDROLOGY... Issued at 216 PM CDT Wed Oct 10 2018 A swath of heavy rain with widespread amounts of 1 to 2 inches and local amounts over 2.5 inches fell across eastern Iowa into far west central IL fell overnight into early this morning. With today's cold frontal passage, the threat of heavy rain has ended. The incoming, more typical fall weather regime will feature systems with less moisture to work with, leading to mainly light rain amounts. However, widespread significant river flooding will remain an issue through at least next week as the runoff from the past couple weeks of very wet weather makes its way through the river system. On the Mississippi River: Moderate to Major flooding is occurring from the Quad Cities downstream to Keokuk with forecasts of Major flooding along the entire stretch persisting through most of next week. The latest forecasts, which are now adjusting to known flow in the river system and no longer have QPF to deal with, have trended toward faster rises, and in some locations, higher crests along this stretch. Just downstream, this flow is still expected to result in Moderate flooding at Gregory Landing. Upstream from the Quad Cities, all sites except Bellevue are forecast to reach at least minor flood stage over the next week. Routed flow from heavy rainfall further upstream across MN and WI results in forecasts of continued rises well into next week. Will maintain a flood warning at Dubuque lock and dam 11 for the strong likelihood of flooding from routed flow developing just beyond the current 7 day forecast. Significant flooding continues along most tributary rivers in eastern Iowa and northwest Illinois. Here are the most significant changes from this morning's forecasts: On the Cedar River, the crest was lowered at Vinton, Cedar Rapids and Conesville. The crest was lowered well over one foot at Cedar Rapids, where the weekend crest is now expected to stay within Moderate category flooding. On the Iowa River, the latest heavy rain axis had more of a direct impact on the basin, resulting in earlier, higher crests from the Coralville dam downstream to Oakville. At Iowa City, the combination of local runoff and adjusted flow out of the reservoir will result in Minor flooding until tonight. On the flip side, the crest at Marengo was adjusted earlier and lowered. On the Skunk River, the river is now forecast to touch Major flood stage at Augusta by Friday. On the Rock River, levels are cresting at Joslin and receding upstream. With less rainfall in the basin than forecasted, levels are now expected to recede faster, but still remain close to previous crests at Joslin and Moline. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ SYNOPSIS...14 SHORT TERM...14 LONG TERM...14 AVIATION...12 HYDROLOGY...Sheets