007 FXUS63 KOAX 272112 AFDOAX Area Forecast Discussion National Weather Service Omaha/Valley NE 312 PM CST Sat Feb 27 2021 ...Updated Forecast Discussion and Hydrology Discussion... .DISCUSSION... Issued at 247 PM CST Sat Feb 27 2021 We will see a chance of rain developing, especially in northeast NE this evening, and that rain will likely change to snow along the NE/SD border. And it's that area that could be in slight deformation zone overnight with light snow diminishing to flurries by daybreak Sunday. Model consensus indicates 1-2" possible for a couple of counties, Knox and Cedar, and even a couple models hint at possible slightly more in the 3-4" range along the SD border. Thus will issue a winter weather advisory for Knox and Cedar counties through 6 am Sunday morning. Farther south, as the inverted trough moves through the are this evening, could see a isolated showers develop. There is just a hint of some very limited mid level instability, with computed 850mb LI slightly negative during the evening. SPC keeps the general thunder outlook south of the area, as does the calibrates SPC HREF model. The SREF hints at a narrow corridor of thunder probabilities, but overall, have removed the mention of any thunder this evening. Where it rains, amounts will be light at less than one tenth of an inch. After slightly cooler days Sunday and Monday with highs mostly in the lower to mid 40s, (albeit still near normal), the remainder of the forecast Tuesday through Saturday looks warm and dry and very mild with highs mostly in the 50s, but a few low 60s here and there as well. && .AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon) Issued at 1128 AM CST Sat Feb 27 2021 VFR conditions initially, but lowering clouds result in MVFR conditions by 00-03z. There will also be a chance of showers by 21z-03z at KOFK, and 00-06Z KLNK/KOMA. There is also a 20% chance of a rumble of thunder at KLNK/KOMA, but not confident enough to include in the aviation forecast at this time. There is also a small chance of measurable snow for northeast NE, but believe any accumulation will remain north of KOFK at this time. && .HYDROLOGY... Issued at 247 PM CST Sat Feb 27 2021 The flood watch remains for the Platte and Elkhorn River basins through Monday. We do have two ongoing ice jams and associated flooding along the Platte River, the first near Schuyler, and the second near Fremont. Flood warnings continue for those two locations with no substantial changes or improvement noted. River observers have reported that lower portions of both rivers were perhaps seeing some clearing out with more free flowing water noticed. And that's good news to allow any additional ice breakup coming downstream to hopefully continue to move through the system. We are continuing to seeing higher flows on the Platte from North Bend downstream, so we know there is likely some ice moving through the channels. We are also seeing stages drop at Waterloo on the Elkhorn River, which confirms the visual observations that ice was clearing out there, and likely making it into the Platte River. Given the high uncertainty of if, or when any additional ice jams could develop, we will continue the flood watch at this time. We did trim a couple of counties in the upper reaches of the Elkhorn River out of the flood watch since river observations there indicate the water seems to be flowing mostly OK, with plenty of room in the banks if something were to happen. And we'll continue to monitor closely, in cooperation with river observers, NRDs, and local Emergency Management to alert of any additional ice jams if they develop. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...Flood Watch through Monday morning for NEZ032-033-042>045- 050>053-067. Winter Weather Advisory from 6 PM this evening to 6 AM CST Sunday for NEZ011-012. IA...None. && $$ DISCUSSION...DeWald AVIATION...DeWald HYDROLOGY...DeWald