textproduct: Hastings

KEY MESSAGES

- Widespread coverage of strong to severe storms is likely this evening to tonight (mainly between 6PM-1AM). All severe hazards will be possible (large hail up to the size of golf balls, damaging wind gusts up to near 70 MPH and an isolated tornado may be possible)

- A few more severe storms (threat concentrated mainly north of I-80) will again be possible Sunday afternoon to evening. Baseball size hail and damaging thunderstorm wind gusts up to 70 MPH may be possible within the strongest storms. A few tornadoes will also be possible.

- A 3rd consecutive day of severe activity will roll into Monday evening, though the threat will mainly be concentrated south and east of the Tri-Cities.

- Near-critical to critical fire weather concerns look return for likely to return to a southwest portion of the area Sunday given strong southerly winds blowing near 20-30 MPH and gusting as high as 30-40 MPH.

- Highs in the mid 80s and 90s today and Sunday will drop to the upper 50s to low 70 Tuesday following the passage of a cold front Monday. A steady increase in highs will likely trail through the end of next week.

UPDATE

Issued at 312 AM CDT Sat May 16 2026

Today...Widespread afternoon to evening severe weather potential.

The chance for severe weather will return each night through Monday with the best potential for more widespread activity occurring this afternoon and tonight. These active next few day comes as an upper- level trough amplifies across the western CONUS. A stationary front that glided south and into Kansas overnight, will be expected to switch directions and shift back north later this afternoon and evening. This feature will likely help trigger off some afternoon and evening severe convection across much of Kansas and Nebraska.

The airmass surging in behind the northward lifting boundary will serve as a source of fuel for these storms as a moist (mid 50s to low 60s dewpoints) and unstable airmass (2,000-3,5000J/kg of CAPE) marches in from behind. In addition, a moodiest amount of shear (40- 50kts of bulk shear) from veering winds and steep low-to-mid level lapse rates (7-9 C/km) point towards an all severe hazard scenario at first (large hail, damaging winds and an isolated tornado possible).

Storms that erupt earlier in the afternoon (6-8PM window) may start out more discrete and supercellular in nature before congealing into an expansive storm cluster later this evening. The best potential for a brief tornado spin up would occur along this earlier window while LCLs are at their lowest points and storm inflow is less likely to be altered from neighboring storms. Storms later on, especially as the nocturnal 50-60kt low-level jet winds up, could quickly morph into a expansive MCS that races east/northeast across much of the area through the rest of the evening and night. Damaging wind will quickly become the primary hazard with the 6z HRRR even suggesting a bowing/QLCS structure forming later on in these storms life cycle. The severe threat should wane after 1AM as the last lingering storms generally drop below severe criteria. A few localized areas of flooding may have to be monitored for locations that receive an extended period of the heavier downpours.

As result of today's conditions, an enhanced risk of severe weather will be in place across our far western portions of the area (areas mainly west of a line from Buffalo to Franklin counties in Nebraska and Phillip county in Kansas) with a slight risk across the rest of the area. Storms will generally have the best potential to materialize across the enhanced risk area. Before any convective activity takes place this afternoon, highs should be on track to reach the mid 80s to low 90s with steady 10-15MPH easterly winds, turning more southeasterly through the day.

Sunday...Potentially heightened severe threat, mainly concentrated north of I-80.

The final shower/storms lingering behind Saturday nights activity should be well clear of the area come Sunday morning. Yet another potentially severe event may also be possible Sunday afternoon to evening. The feature of note that will drive the storm chances Sunday will the the presence of a strengthening surface low across western Kansas/Nebraska. The track of this surface cyclone will be crucial for identifying where the warm sector will lie and where the peak daytime destabilization will take place (broad area of 2,000- 3,000J/kg CAPE with 7-9 C/km low-to-mid level lapse rates).

The latest CAM guidance continues to show that a triple point (where the cold front, warm front and dryline meet) tracking right through the heart of south central Nebraska during the afternoon. All of the essential ingredients needed for a higher end type of severe event currently look to be present (instability, shear and moisture). The biggest question yet to be fully understood is where storms will initialize and how expansive storm coverage may become.

The latest 6z HRRR guidance continues to keep a majority of the activity further northward and closer to the triple point rather than along the dryline stretched out to the south (where the NAMNEST has been suggesting). If this scenario is actualized, the better storm potential would be mainly concentrated north of I-80 with very few storms elsewhere. The Day-2 SPC convective outlook keeps a majority of central Nebraska included in an enhanced risk.

Temperatures for Sunday could warm up to the 90s to maybe even the low triple digit across a few north central Kansas locations. Given the condensed pressure gradient from the deepening surface low, gusty southerly winds up to 30-40 MPH look to file in across much of north central Kansas and east central Nebraska. The gusty winds in combination with a fairly prevalent dry slot protruding along the southwest trail of the surface low looks likely to bring near critical to critical fire weather concerns back to our far southern Nebraska and north central Kansas areas for Sunday afternoon.

DISCUSSION

Issued at 427 PM CDT Fri May 15 2026

This evening-overnight: No major changes in the latest thinking regarding severe weather potential. Still appears the main threat area will focus in the far E/SE portions of the forecast area...along and ahead of a weak boundary. There's not a lot of temperature differences on either side, and winds are weak such that convergence isn't very strong either. Main differentiators is moisture, with dew points in the mid 50s in places like Hebron vs. lower 30s in the Tri-Cities. It got quite warm/hot out there today, so areas that do have decent low level moisture have moderate instability in the 1000-2000 J/kg range amidst steep mid level lapse rates over 8 C/km. Wind shear is modest, but sufficient, for organized deep convection with latest SPC mesoA page indicating 30-40kt of effective deep layer shear, decreasing with SW extent. Forecast soundings and sfc T/Td spreads >30 degrees suggest inverted-V profiles/elevated bases and wind gusts as the primary severe threat. The steep mid level lapse rates and modest shear also support a severe hail threat, particularly in the initial cores. Expect fairly quiet conditions between midnight through early afternoon Saturday.

Saturday PM: The next round of potential severe weather will come as early as late Saturday afternoon, but more likely during the evening into early overnight hours. A deepening upper trough over the W CONUS will begin to exert it's influence by later in the day in the form of modest height falls and difluent and divergent upper level flow. Latest CAMs appear to be converging on a general solution where today's weak boundary stalls out, then lifts northward as a warm front during the afternoon, reaching central Nebraska by 00Z Sunday. Most likely area for convective initiation will favor areas to our west along the High Plains within a broad swath of Erly upslope flow and closer to the arriving height falls. This activity will likely congeal into one or two MCSs that roll E/NE during the late evening and overnight, sustained by a strong LLJ increasing to 50-60kt by 03Z. Moderate to strong instability (MLCAPE as high as 2000-3000 J/kg), strong effective deep layer shear (40-50kt) - including strong upper level storm-relative flow/venting - and very steep low to mid level lapse rates all suggest potential for upper- end type hail and damaging wind. In fact, wind-driven large hail could be a concern. Will also need to watch the southern end of an expected MCS or any embedded supercells, esp ones that interact with the warm front, for a few tornadoes. This would be most concerning in the 00-03Z time frame as LCLs lower and low level SRH ramps up with the aforementioned LLJ.

The above scenario is the one that appears to be most probable at this time (MCS rolling off the High Plains later in the day with primarily a hail/wind threat), but isolated late afternoon CI eastward into our area along the warm front is also plausible...a la the 18Z HRRR. This scenario is highly conditional due to some capping and weaker forcing, but potentially high- impact, if it were to pan out. This scenario would increase the high- end hail threat (up to around baseball size) and also probably the tornado threat. Want to see more CAM consistency before ramping up this messaging.

Sunday: appears any convection from Saturday night will have shifted N/NE of the area by sunrise Sunday AM...setting the stage for strong destabilization of a broadening warm sector. In general, appears there will be most of the ingredients necessary for a higher-end severe weather threat, including strong tornadoes...but as always, the details matter and are still murky this far out. With the lack of AM convection, don't think instability will be an issue, and the arrival time of stronger upper level forcing appears to be well-timed towards the peak heating hours. So even through mid level temps will be quite warm (14C+) early in the day...some cooling/height falls towards 00Z Mon along with strong destabilization should be enough to support robust CI. Once storms form, should have most/all of the ingredients in place for significant severe weather...with the main uncertainty lying in the location of a likely triple point (closer to Lexington or closer to Tri- Cities) and QUALITY of boundary layer moisture. Some models (e.g. 12Z EC) really mix the BL and lowers Tds into the 50s...whereas the NAM shields the BL a bit more and maintains mid to upper 60s Tds through the late afternoon. RRFS is somewhat in between. Thus...this casts some uncertainty on mainly the tornado threat...at least early on in the convective cycle. Threat could increase in time - even per the 12Z EC - with gradual lowering of LCLs and increasing low level shear. Not sure what convective mode would be by then, though. Still plenty of time to hash out those details.

System as a whole has trended slower...which brings more of our area into play for another round of significant severe weather potential on Monday. This looks to be our last day (for at least a few days) of severe weather threat as the upper trough finally moves through Monday night. Haven't looked into details of Monday and beyond very much today since there's plenty of impactful weather in the short term.

One last thing...still monitoring the potential for a wedge of critical fire weather conditions to punch into far W/SW zones behind the dry line Sunday afternoon. Phillips down into Rooks County would be most at risk, even if they see rain Saturday night, as much of the fine (1hr) fuels are still susceptible to large fire growth.

AVIATION /06Z TAFS THROUGH 06Z SUNDAY/

Issued at 1128 PM CDT Fri May 15 2026

For KGRI/KEAR Airports:

VFR conditions for the first 12 to 15 hours will give way to a developing showers and thunderstorm risk in the last part of the forecast. Initially, winds have turned northeast behind a cold front and maintained around 12 kts. This should continue overnight and Saturday morning though windspeeds should taper off a bit as pressure rises fade. We expect a mostly clear sky overnight but increasing mid/high clouds thorugh the midday hours at both airports on Saturday. The main story later Saturday will be developing showers and thunderstorms in the late afternoon & evening. Increasing low level moisture and advancing will spell fairly widespread coverage of showers and storms after 3-4 pm and continue through the evenings. Look for occasionally MVFR ceilings as more steady preciptiation sets up.

GID WATCHES/WARNINGS/ADVISORIES

NE...None. KS...None.