Area Forecast Discussion
Issued by NWS Hastings, NE
Issued by NWS Hastings, NE
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850 FXUS63 KGID 011129 AFDGID Area Forecast Discussion National Weather Service Hastings NE 629 AM CDT Wed May 1 2024 .KEY MESSAGES... - Severe weather remains possible today, and the peak timeframe for severe storms is between 6pm and 3am. Although some strong to marginally severe storms are possible prior to that. - Large hail will be the primary threat with any storms that develop today into tonight. Isolated damaging wind gusts are also possible, but the threat for tornadoes has decreased for our local area. - Localized flooding is also possible, mainly during the overnight hours tonight. - More chances for thunderstorms through the next week, especially Friday night, and again Sunday night through Monday night. && .DISCUSSION... Issued at 427 AM CDT Wed May 1 2024 A band of rain showers stretches form NW Colorado through central and north-central Nebraska. This activity should continue to lift northward out of the area by sunrise or shortly thereafter. As it does, returning moisture should allow additional showers and thunderstorms to develop from south to north this morning into early afternoon. These storms will have ample shear to work with (effective shear of 40-60kts). Instability will start off rather limited, but elevated MUCAPE values could approach 1000 J/kg by this afternoon. As instability increases, a few of theses storms could produce marginally severe hail. Looking later into the afternoon, confidence has increased that the surface warm front (and any meaningful SBCAPE) will remain well to our south. As such, the threat for tornadoes in the local area has diminished. That said, there is still considerable variance amongst the CAMs on how exactly this evening and overnight will play out. Some solutions develop some elevated storms in/near our KS counties as early as 6-7pm, but others keep our area relatively quiet until more convection develops on the LLJ and approaching cold front overnight (9-10pm onwards). Regardless of exact timing/evolution, the main severe threat continues to be hail. As mentioned above, there is plenty of shear, and MUCAPE will continue to increase through the evening, aided by 40-50kt winds at 850mb. If storms can organize into some west to east propagating line segments, some localized damaging winds are possible, as well. Additionally, the multiple rounds of thunderstorms could result in localized excessive rain and flooding. That said, this threat is not overly high, and the lack of consensus amongst CAMs, reduces confidence in highlighting any specific locations. The 00Z HREF shows only ~30% neighborhood probabilities for 2.00" or more of rain through Thursday morning, and 6-hour flash-flood guidance is generally above 2.50" (even areas that received heavy rain last week). Storm intensity and coverage should start to decrease by around 3am. A few showers/storms could linger on Thursday, but most locations will stay dry. Increasingly dry air may allow northwestern portions of the area (especially Dawson and Valley counties) to dip into the 30s and see some patchy frost Thursday night. The overall pattern remains pretty active through the weekend and into early next week. The first time period to watch will be Friday night into Saturday morning as a shortwave brings a 60-70% chance for rain and thunderstorms to the area. Instability is somewhat limited, but some marginally severe hail/wind cannot be ruled out. A stronger upper low then is expected to push into the region late Sunday into Monday. After today, this is the timeframe that is most favorable for severe weather per the CSU-MLP severe probabilities. && .AVIATION /12Z TAFS THROUGH 12Z THURSDAY/... Issued at 624 AM CDT Wed May 1 2024 Scattered showers are starting to develop south and west of EAR/GRI. This should spread northward to the TAF sites by midday. Ceilings will gradually lower through the afternoon and evening, eventually reaching IFR late in the evening. GRI/EAR will have a break in showers/t-storms in the evening before additional thunderstorms develop and push through EAR/GRI later overnight. && .GID WATCHES/WARNINGS/ADVISORIES... NE...None. KS...None. && $$ DISCUSSION...Mangels AVIATION...Mangels