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FXUS63 KOAX 300729 AFDOAX Area Forecast Discussion National Weather Service Omaha/Valley NE 229 AM CDT Tue May 30 2023 ...Updated Forecast Discussion... .DISCUSSION... Issued at 230 AM CDT Tue May 30 2023 Key Messages: - We are moving into a more active period with precipitation chances just about every day through the forecast. We have watched the MCS across central NE slowly weaken as it inches eastward overnight, although it continues to dissipate, and there may not be much if anything left north of the Platte River as it moves into our area through daybreak. Some very beneficial rainfall did occur over small portions of northeast NE yesterday evening and early this morning where Albion picked up about 3/4" of rain. And heavier downpours are starting to develop west of Highway 77 south of the Platte River this morning as well. The forecast this morning will still have isolated chances for a shower, with precipitation chances increasing again to 30-40% this afternoon as the remnants of the MCV could be in the Missouri River valley during the afternoon. And, we may also have the remains of the very weak subtle wave aloft to help fire a few storms as well. Honestly, though, the models are showing mixed signals, with some remaining dry, while the Highres Cams are all over the place on where and when the convection develops, so confidence in the details remains low, even just 12 hours in advance. My best confidence will be along and east of the Missouri River with a line of storms potentially firing 12 pm through 6 pm. With some morning cloud cover likely giving way to sunshine through the day, high temperatures should still reach the lower to mid 80s in the Missouri River valley region, and the mid to upper 80s elsewhere. SPC has placed the entire region in a marginal risk of severe storms with a 5% chance of gusty winds and hail, and that seems OK along and east of the Missouri River, but again, even confidence in a storm that might reach severe levels is on the lower side. In the weak subsidence of the wave, the HRRR is trending dryer now for the evening, but as the next subtle wave approaches from the west overnight, some of the models are developing additional scattered storms, so Pops will remain in the 30-50% range. WPC has also placed the entire region in marginal 5% risk of heavy rainfall, but given our recent dryness, am not overly concerned for any widespread flooding at this time because we have been so dry lately. And then the forecast for the next 7 days will include a daily chance of showers and storms somewhere in our forecast area as a series of waves affect the central US. But at the same time, it won't be a complete washout, and some areas may receive rain one day and not another. This is also the type of pattern that could end more dry than you might expect with hit and miss chances for meaningful rain. Given our deepening drought, it would be nice to see some generous rainfall amounts over the next week. WPC 5-day forecast amounts range anywhere from 1/4" to as much as 2" for some areas. But the confidence in any one location receiving more than any other remains quite low. && .AVIATION...(For the 06Z TAFS through 06Z Tuesday night) Issued at 1144 PM CDT Mon May 29 2023 VFR conditions will prevail through the period. Thunderstorms look likely to remain west of the terminals over central Nebraska. It's currently raining at KOFK which should end for the night by 07Z. Pockets of light rain may move through KOMA and KLNK overnight, but no restrictions expected. Winds at will remain out of the south or southwest overnight tonight around 7-10 kt. Additional pockets of light rain will be possible through the morning hours on Tuesday, with VFR conditions continuing. We'll see another chance for isolated to scattered thunderstorms Tuesday afternoon with no organized boundary to help narrow down where they will develop. Have not included in the TAF until confidence increases that they will actually impact the terminals. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...None. IA...None. && $$ DISCUSSION...DeWald AVIATION...McCoy