####018005569#### FXUS63 KOAX 060246 AFDOAX Area Forecast Discussion National Weather Service Omaha/Valley NE 946 PM CDT Fri Jun 5 2026 .KEY MESSAGES... - Strong to severe thunderstorms continue tonight as a front moves through the region. Large hail, damaging winds, an isolated tornado, and heavy rainfall resulting in flash flooding will be possible with any thunderstorms that develop. - Saturday's highs will reach the upper 80s and lower 90s with isolated showers and thunderstorms, before a slight cooldown and more widespread thunderstorms on Sunday. - A pattern shift over the weekend will result in several disturbances moving through the region heading into next week. Daily chances for precipitation are expected for at least a portion of the area each day. Additionally, temperatures climb well into the 90s with potential excessive heat concerns. && .UPDATE... Issued at 945 PM CDT Fri Jun 5 2026 General lack of thunderstorm reports suggest storms so far have mostly underperformed. As storm coverage increases, storm interactions have been detrimental. Expect to see fewer severe warnings over the next few hours as flood concerns continue to grow. Slow storm motions have left some areas with accumulations of 2-5" so far across parts of southern Lancaster and southwestern Seward County. The complex as a whole is meandering east with a slight northern component to its motion. As a result, flooding concerns for the Omaha metro are increasing. Guidance continues to suggest this complex lasting through much of the night before dissipating around sunrise. Have added some patchy fog to river valleys, especially in western Iowa by sunrise. && .DISCUSSION... Issued at 109 PM CDT Fri Jun 5 2026 Several inches of rainfall occurred across portions of Southeast Nebraska and Southwest Iowa Thursday afternoon into early this morning. This system is now moving east of the region, but has slowly pushed a front into the area. This front becomes the focal point for our weather this evening and tonight. In the meantime, a few elevated showers and thunderstorms linger over Northeast Nebraska and west-central Iowa early this afternoon. Impacts from these should be limited with perhaps a brief downpour possible. Subsidence increases this afternoon behind the aforementioned system, resulting in clearing skies. Highs rise well into the 80s under the plentiful sunshine. With a cap in place, instability builds through the afternoon, likely exceeding 3000 J/Kg by evening. This instability, coupled with the front, and increasing westerlies with a passing disturbance support thunderstorm development by late evening. With plenty of instability and sufficient shear an all severe hazards threat is expected. This threat should gradually lessen tonight as thunderstorm clustering and low-level stability increase. The threat transitions to more of a flash flooding concern. Many areas across Southeast Nebraska and Southwest Iowa received 2-4" of rainfall already. An addition 1-2" appears likely for much of these same areas with perhaps locally higher amounts of 2-4" possible. A Flash Flood Watch has been issued through tonight with this expectation. Other areas, including Beatrice, up through Omaha, and into Pottawatomie County may also see significant rainfall, but lingering uncertainty on the heaviest band of thunderstorms and more limited rainfall yesterday casts doubt on widespread flooding potential at this time. Heading into Saturday, a mostly dry day is expected for many as temperatures warm through the upper 80s and low 90s. A few widely scattered showers and thunderstorms may sneak into Southeast Nebraska and Southwest Iowa later in the afternoon into the evening. Temperatures cool slightly on Sunday as more widespread showers and thunderstorms are expected in association with a trough lifting through the Plains into the Mississippi River Valley. Beyond this weekend, a pattern shift takes hold. Mid-level ridging overspreads much of the central and eastern CONUS with troughing over the western CONUS. These changes support an increase in temperatures well into the 90s by the middle of next week, perhaps near 100 for some. This may lead to excessive heat concerns and will be monitored closely. With the trough to the west, a series of disturbances round the ridge and should support daily shower and thunderstorm potential for at least some of the area. As a result, it may feel closer to July then mid-June next week. && .AVIATION /00Z TAFS THROUGH 00Z SUNDAY/... Issued at 529 PM CDT Fri Jun 5 2026 Light southeasterly winds are forecast this evening with the exception of where strong thunderstorm winds develop. Storms are most likely in the Lincoln and Omaha areas. Have kept KOFK dry through the TAF period. Expect the storms to be slow to move away from LNK and OMA once they develop. The 3-4 hour windows currently highlighting the threat of TSRA at LNK and OMA may not be long enough as the threat of storms will continue until at least midnight. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...Flood Watch until 7 AM CDT Saturday for NEZ050>053-065>068-078- 088>093. IA...Flood Watch until 7 AM CDT Saturday for IAZ069-079-080-090-091. && $$ UPDATE...Nicolaisen DISCUSSION...Chehak AVIATION...Nicolaisen ####018004374#### FXUS63 KFGF 060248 AFDFGF Area Forecast Discussion National Weather Service Grand Forks ND 948 PM CDT Fri Jun 5 2026 .KEY MESSAGES... - More chances for showers and storms Sunday night, as well as mid to late next week. Some storms could be severe. - Potential for heat-related impacts Sunday, and mid to late next week. && .DISCUSSION... Issued at 246 PM CDT Fri Jun 5 2026 ...Synopsis... The main upper trough continues to swing through Ontario, but several weak vort maxes/shortwaves are still coming down the backside of it. One main vort is moving through the southern Red River Valley and another is headed towards the Devils Lake Basin. Discussion of thunderstorm risk this afternoon and evening continued in the next section below. Upper ridging moves quickly into the Plains and Upper Midwest tomorrow, then pushes towards the Great Lake by Sunday. Pretty amplified southwesterly flow aloft sets up Sunday and continues into the upcoming week. One lead shortwave starts to move through late Sunday into Monday. Timing of such minor shortwaves always uncertain, but ensemble members in pretty decent agreement on bringing another shortwave out sometime mid-week. Upper troughing moves out into the Northern Plains by the end of the week either phased or as a weak cut off low, keeping active pattern going with perhaps some slightly cooler temperatures. ...Marginal severe risk this afternoon and evening... Vort max over the southern Red River Valley will be the one to watch this afternoon, with ML CAPE up around 1000-1500 J/kg while the more northern weak shortwave just has around 500 J/kg to work with. Effective shear is also higher in west central MN, with around 30 kts vs 20 kts. Storms that have been going up in Wilkin/western Otter Tail counties have been pretty disorganized so far, but can't completely rule out a few cells getting high enough to produce some 1 inch hail or gusts up to 60 mph. WoFS run has the best chances for strong updraft helicities just to the southeast of our CWA during the next few hours, but with continued weak upper forcing and some instability to work with don't want to rule out development further northwest. ...Severe threat late Sunday into next week... With an extended period of southwesterly flow aloft, there should be plenty of time for moist, unstable air to build over the Northern Plains. A lot of variation in the ensemble members in exactly how much instability, but even the lower percentiles for CAPE at KDVL have over 1500 J/kg with the higher end of the ensemble approaching 4000 J/kg. With the pretty amplified flow on Sunday, best chances for severe will be for our northwestern counties before storms move off into Canada. After that system pulls off to the east, surface winds quickly return to the south ahead of the next system. By Wednesday, spread for the CAPE values narrows a bit, with most of the ensemble members showing over 1700 J/kg and many between 2000-3000 J/kg. for several days next week, severe chances will be above 15 percent, so will have to keep a close eye on the more active pattern. ...Heat Sunday and again later in the week... ECMWF EFI shows a strong signal for warmer than average temperatures for the entire seven day period, with particularly high values on Sunday and Wednesday. With southeasterly winds the dew points will be on the rise. Probabilistic heat risk is around 20 to 30 percent chance for major impacts (excessive heat warning criteria) Sunday in the Red River Valley, and even higher values in west central MN for Wednesday. Will have to keep a close eye on heat impacts as we head into the day 3-7 period. && .AVIATION /03Z TAFS THROUGH 06Z SUNDAY/... Issued at 947 PM CDT Fri Jun 5 2026 VFR will prevail throughout the TAF period. Light winds overnight will become southerly on Saturday at up to 12 knots, a bit stronger in Devils Lake at up to 15 knots with a few gusts up to 25 knots or so. There is a very low chance for fog to develop Saturday morning, therefore no inclusion in the TAF at this time. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...None. MN...None. && $$ DISCUSSION...JR AVIATION...Rafferty