308 FXUS63 KOAX 171954 AFDOAXArea Forecast Discussion National Weather Service Omaha/Valley NE 254 PM CDT Wed Sep 17 2025
.KEY MESSAGES...
- Scattered off-and-on showers and storms are expected through this evening. The best chance for additional rainfall will be over northeast Nebraska and southwest Iowa. There is a small chance for a severe storm.
- Another round of scattered showers and thunderstorms is expected on Thursday, and perhaps once again on Friday. Severe weather is unlikely.
- Cooler temperatures in the 70s through late week, with warming temperatures into the 80s returning this weekend into early next week.
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.DISCUSSION... Issued at 254 PM CDT Wed Sep 17 2025
A broad trough centered over the central and northern Great Plains continues to inch towards the east early this afternoon. Embedded within this larger feature are several shortwave troughs. These shortwaves will slowly circulate around each other within the broad trough through late week. One of these troughs is currently located over central Nebraska this afternoon. This feature caused the widespread morning showers and thunderstorms earlier this morning. Lingering low clouds from this morning`s rainfall has stunted daytime heating across the region with most remaining cooler than expected today. These cooler temperatures are likely to limit afternoon destabilization, which may result in more limited rainfall through this evening. That being said, with the shortwave off to the west, additional showers and thunderstorms are expected to develop in an arching band late this afternoon and evening. This band will lift northeast along with the shortwave trough tonight. While instability is limited, plentiful near surface vorticity and cold temperatures aloft may result in an isolated severe thunderstorm. Additional rainfall amounts are likely to remain below half an inch for areas that receive additional showers and thunderstorms.
Tomorrow into Friday, the broad trough continues to slowly move towards the east, but glancing passes from the embedded shortwaves maintains at least a low chance of showers and thunderstorms each day, mainly during the afternoon and evening. This activity is expected to be less widespread with a drier airmass gradually moving into the region as the area transitions towards the backside of the system. Instability will be limited through the late week and severe weather is unlikely at this time. Additional rainfall amounts up to around a quarter of an inch may be possible for those that see rain. Otherwise, enjoy the cooler temperatures while they last.
By this weekend and into early next week, drier weather and warming temperatures dominate the forecast. 80s return to portions of the region during this time. These temperatures are slightly above normal for this time of year. Additional rain chances are limited as mostly sunny to partly cloudy skies are largely maintained as weak ridging takes over behind the departing trough. While the broad pattern favors ridging across our neck of the woods, a weak disturbance or two may bring at least a low chance of thunderstorms to portions of the area by late weekend and towards the middle of next week. As is typical with late summer convection, exact details are hard to determine and will continue to be monitored as the forecast draws closer.
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.AVIATION /18Z TAFS THROUGH 18Z THURSDAY/... Issued at 1221 PM CDT Wed Sep 17 2025
Showers and isolated thunderstorms continue to lift towards the northeast early this afternoon. Ongoing rainfall will slowly weaken and end early this afternoon. OFK is nearest the approaching low pressure system resulting in lower MVFR ceilings currently. Elsewhere, VFR conditions are expected to remain prevailing. Winds are generally light and southeasterly, but these gradually veer throughout the day. Additional afternoon and evening scattered showers and isolated thunderstorms may develop, but confidence is low (10-40%). With low confidence and scattered coverage of this activity, will not mention in the TAF at this time. Fog may develop during the morning hours between 10-14Z, but this is towards the end of the forecast and confidence remains low. Will continue to monitor for later TAF forecasts.
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.OAX WATCHES/WARNINGS/ADVISORIES... NE...None. IA...None.
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DISCUSSION...Chehak AVIATION...Chehak
NWS OAX Office Area Forecast Discussion