textproduct: Hastings

KEY MESSAGES

- Isolated to scattered storms (possibly some severe), are expected to move through the area during the daytime today (mainly 11am to 4pm).

- Another round of strong to severe storms may redevelop this evening into tonight (roughly 10pm to 2am).

- The daytime of Saturday should remain dry, but weakening showers/storms arrive from the west late Saturday night into Sunday morning.

UPDATE

Issued at 318 AM CDT Fri Aug 21 2026

The main concern in the near term is the potential for multiple rounds of storms today into tonight. Unfortunately, confidence in exact details remain quite uncertain due to high variability in the CAMs.

Recent satellite depicts a slowly increasing area of midlevel clouds over western Nebraska into southwest South Dakota in association with weak warm-air advection. CAMs generally favor this to continue to develop through the morning hours. Unfortunately, there is not much agreement on the spatial coverage, intensity, or exact timing. The 00Z HRRR depicted a relatively robust line of storms in the 11am to 3pm timeframe, but the 06Z run has backed off on this considerably. IF storms develop, convective parameters would support large hail and damaging wind.

The potential for severe convection late this evening into tonight largely depends on how things play out during the daytime today. Unsurprisingly, the 00Z HRRR is much more reserved with evening development as the daytime convection would help stabilize a large portion of the area. Of course, the 06Z run has "flipped the script," with the decreased daytime coverage resulting in more widespread and intense thunderstorms late in the evening and overnight.

After any lingering showers/storms depart the area Saturday morning, the rest of the daytime looks to be dry and pleasant. Chances for thunderstorms return late Saturday night into Sunday morning as convection rolls out of Colorado/Wyoming. That said, this is likely to be on a weakening trend as it approaches the area in the 1-3am timeframe.

DISCUSSION

Issued at 128 PM CDT Thu Aug 20 2026

TODAY Weak convergence amid the NW flow aloft will allow for clear skies and highs to increase into the 80s-low 90s this afternoon. Within this flow aloft is a shortwave disturbance along the MN/Canadian border, supporting a weak surface low and a weak cold front stretched across the Dakotas. This front is expected to move southward, potentially forcing some isolated thunderstorms into central Nebraska after 4PM, suggested by earlier model guidance. However, it is uncertain how far the cold front will make it given the marginal upper-level support. In fact, recent HRRR and RRFS guidance hast this front stalling out in Northern Nebraska, keeping thunderstorm chances limited to North of I80. Should a thunderstorm form, CAPE values around 2000-2500 J/kg and shear in excess of 40 kts could allow some strong to severe storms, with main hazards being golf ball sized hail and strong wind gusts of 60+ MPH. While a few thunderstorms are possible, most of the area will remain dry this evening.

TOMORROW (Friday) While not overly confident, there is a chance of fog tomorrow morning, mainly for the eastern half of the area, with ample low-level moisture and weak surface winds. However, model guidance is not as aggressive with this fog as they were this morning. The main uncertainty is the coverage of these evening storms and if skies are able to clear for sufficient radiative cooling. Additionally, showers/thunderstorms are possible (15-25%) for the NE portions of the area tomorrow morning between 3-8AM due to some weak WAA advection at 850 mb. A few of these may be on the strong to severe side. Tomorrow afternoon is expected to be clear and dry, allowing highs to peak in the upper 80s to mid 90s.

Additional thunderstorms are possible tomorrow during the evening to overnight hours. Recent model guidance suggests isolated thunderstorm development to the North-Northwest of the area around 6- 8PM, congealing into a complex somewhere over the area. Some of these storms may be strong to severe, as models are indicating 2500+ J/kg of SBCAPE and 45+ kt of 0-6km shear. However, the location and timing of this thunderstorm development remains uncertain.

SATURDAY AND BEYOND As the upper level ridge continues to expand across the intermountain west, mostly dry conditions are expected Saturday, with highs in the 80s. However, the chance for showers/thunderstorms returns Saturday night into Sunday morning as a weak shortwave emerges from the NW flow aloft. Additional off and on showers/thunderstorms are possible into early next week as a broader trough approaches from the West.

AVIATION /12Z TAFS THROUGH 12Z SATURDAY/

Issued at 625 AM CDT Fri Aug 21 2026

For KGRI/KEAR Airports:

A small cluster of t-storms near and northeast of BBW will continue to move through south-central Nebraska this morning. Another round of thunderstorms is expected impact portions of the area late this evening into tonight. Otherwise VFR conditions are expected to prevail.

Winds remain light and variable through the period, although could be enhanced by thunderstorm outflow at times.

GID WATCHES/WARNINGS/ADVISORIES

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