textproduct: Hastings

KEY MESSAGES

- Thunderstorm concerns tonight: Primarily between 11 PM-5 AM, mainly the northern 1/3rd or so of our forecast area (CWA)...counties mainly along but especially north of I-80...will be "under the gun" for a complex of strong to possibly severe storms to push through from west-to-east. Damaging winds up to ~ 65 MPH the primary threat. - Thunderstorm concerns Thursday evening-night: Mainly between 7 PM-2 AM, our entire CWA will be prone to seeing at least isolated/scattered storms...a few of which could be severe.

- Heat concerns mainly in our KS counties: A Heat Advisory remains in effect until 9 PM this evening for all 6 of our KS counties, with this Advisory now extended until 9 PM Thursday for the southern-most three counties (Rooks/Osborne/Mitchell), as these counties are most favored to see another round of 105+ heat index.

- Longer term rain/thunderstorm trends (beyond Thurs night): Our forecast remains "littered" with various/intermittent (and mostly lower confidence) shower/thunderstorm chances...bringing beneficial rain but also likely occasional severe weather.

- Temperature overview: Overall (and aside from our KS zones especially Thursday), the next week will feature a fairly "typical" mid-August pattern, with high temps mainly 80s and lows mainly 60s (not necessarily "sold" on highs only in the 70s many areas Sunday-Monday)

DISCUSSION

Issued at 503 PM CDT Wed Aug 12 2026

-- FORECAST CHANGES OF NOTE/BIG PICTURE COMMENTS/UNCERTAINTIES: - No truly major changes of note versus previous 7-day "forecast package", as summing things up in the shortest way possible: We remain in a seasonably-active summer pattern, marked by various/intermittent rain and thunderstorm chances (occasionally severe), along with fairly typical temps by mid- August standards.

- As for uncertainties, there are a few worth noting, ranging from very short term, to longer term: 1) Just how far south in our CWA will any severe storm threat actually extend tonight? This forecaster continues to think that SPC is probably at least 1-2 counties too generously south with its official Slight Risk (level 2 of 5 area), as various high- res models are fairly insistent that the MAIN threat area should be MAINLY north of I-80.

2) In the longer term, am not overly-comfortable with Saturday night currently sporting such high rain chances/PoPs (mainly 60-70%) that far out in time, but at least for now, "on paper" this appears to be one of the better chances for much of our CWA (not just parts of it) to pick up some decent rain.

3) Our official high temperature forecast calls for much of our area (mainly Nebraska) only reaching the 70s Sunday-Monday. However, am thinking we might be aiming a little TOO cool here, as latest set of model guidance suggests 80s are probably more likely (unless of course it ends up being particularly cloudy/rainy.

-- 7-DAY FORECAST CHRONOLOGICAL RUNDOWN (through Wed. Aug. 19): - CURRENT/RECENT WEATHER SCENE AS OF 4 PM: Not that we've heard ANY complaints, but except for perhaps our far southern counties in KS, high temps are on track to "underachieve" by a few-to-several degrees versus earlier forecasts, as fairly widespread coverage of mid-level clouds and a smattering of high-based showers/weak thunderstorms (most weak storms were this morning) have continue to percolate over our CWA. As a result, actual high temps are on track to "only" top out a few degrees either side of 90 in most of our CWA, with any mid-upper 90s to perhaps low-100s confined to mainly our KS counties (particularly our "bottom three"). Directly related to this, heat index readings have also been held down somewhat, with any 100-105+ values mostly confined to our KS counties along with the Furnas County area. Will let the previously- issued Heat Advisory "ride" through 9 PM for all 6 of our KS counties, but in reality only parts of our bottom three (Rooks/Osborne/Mitchell) probably stand a chance of reaching official criteria of 105+.

In the big picture aloft, water vapor satellite imagery and short term model data confirm that our area resides under generally west-southwesterly flow aloft, as we reside in the proverbial "ring of fire" zone along the northern periphery of a ridge/high pressure centered mainly over OK/TX. At the surface, the vast majority of our CWA resides north of a rather sharp, west-east oriented quasi-stationary front that lies across northern KS. To the north of this boundary, easterly breezes generally 10-15 MPH prevail, while to the south of this front (which does clip at least southern parts of Rooks/Osborne/Mitchell counties in our far south,more southerly breezes prevail with temperatures 100+ degrees.

- THIS EVENING-OVERNIGHT: By FAR the main concern is a chance for a complex/cluster of strong to perhaps severe storms to track across mainly the northern 1/3rd of our CWA mainly between 11 PM-5 AM. Leaning heavily on latest higher-res models such as HRRR/RRFS, while some very spotty high-based showers could continue into early evening mainly in our southern counties (near/south of the KS border), at least the vast majority of our CWA should remain dry/thunderstorm-free until at least 11 PM (prior to this, initially more isolated strong/severe storms currently developing out near the NE/WY/CO border area will gradually grow "upscale" into a larger complex as it approaches our CWA). Once storms arrive (again, MOST favored north of I-80 but with at least spotty/isolated activity perhaps as far south as near the state line), the "million dollar question" is how severe they might be? While deep-layer shear will be fairly modest (mainly around 35KT or less), the presence of at least 1000-2000 J/kg instability/CAPE and convergence along the nose/exit region of a somewhat strong southerly low level jet (LLJ) will surely give storms a chance to provide somewhat of a punch, especially IF they are able to maintain a notable cold pool/outflow surge. Of greatest concern are potential wind gusts up to ~ 65 MPH, with a lesser threat of hail up to around quarter size. A few places could get a quick 1-2" of rain, but fairly progressive motion of the complex should limit flooding potential. By around 5 AM, the main complex should be fairly cleanly departed east of our CWA, ending any potential severe threat, although some lingering spotty showers/weak storms remain quite possible.

In other departments, low temps tonight aimed from mid 60s northwest to low-mid 70s southeast. Depending on how aggressively convective outflow surges south across the area, much of our CWA could very well see at least a brief blast of at least 25-35 MPH winds out of the north-northeast...even well- south of where actual rain falls/storms track.

- THURSDAY DAYTIME (through around 7 PM): Other than perhaps some lingering light showers/sprinkles mainly in the morning behind the departing complex, the vast majority of our CWA should have a dry day. The tricky part will be cloud cover and resultant temps/heat index, as although we are already forecasting a rather sharp gradient/divide in high temps across our CWA (ranging from only low 80s north-northwest...to mid 80s central...to mid-upper 90s and even some 100s far south- southeast, the presence of a potentially fairly solid deck of lower clouds over our Nebraska counties could make this temperature gradient even sharper than currently depicted. At any rate, based on our "best attempt" at the temperature/dewpoint forecast, especially our KS counties (but also perhaps Thayer/Nuckolls counties area in Nebraska) has a good chance of reaching 100+ heat index, with particularly our bottom three counties (Rooks/Osborne/Mitchell) more favored to reach at least 105-110 heat index. As a result, have extended Heat Advisory into these counties through 9 PM, and cannot rule out night shift perhaps adding a few more counties based on latest model trends. Otherwise, aside from our far southern areas, most of our CWA will be a touch breezy out of the northeast...sustained speeds commonly around 15 MPH/gusts 20+ MPH.

- THURSDAY EVENING-OVERNIGHT (after 7 PM): Another night, another chance for thunderstorms (a few possibly severe). Although details still need sorted out, confidence is gradually increasing that at least isolated-to-scattered storms will gradually invade our CWA from southwest-to-northeast during the evening, gradually weakening/dissipating during the later night hours. Although this convection will likely be a bit more elevated (above the shallow surface front) compared to storms tonight, instability/shear appear sufficient for at least marginally severe storm, and cannot argue with SPC assigning a Marginal Risk (level 1 of 5) to our entire CWA). Low temps aimed just barely cooler than tonight...mainly mid 60s northwest to upper 60s-low 70s southeast.

- FRIDAY-FRIDAY NIGHT: In some ways, it's "rinse repeat", although admittedly already by this time confidence in "finer details" starts to wane. Much of the day could feature at least spotty showers/weak storms in the wake of the previous overnight activity, although much of the afternoon-evening is likely dry before somewhat better storm chances arrive later overnight. Again, SPC has assigned a Marginal Risk of severe to almost our entire CWA. Temperature- wise, highs in most of our Nebraska counties will be similar to Thursday (mainly 80s), but our KS zones will finally catch a bit more relief, with highs "only" low-mid 90s most places, and heat index expected to be at least slightly short of Advisory criteria (although 100+ values still possible especially far southeast). Lows Friday night mainly mid-upper 60s.

- SATURDAY-SUNDAY (the weekend): Our active pattern continues, with various rain/thunderstorm chances...overall highest Saturday night, although details remain murky for sure. Aloft, our flow transitions from more southwesterly back to more west-northwesterly...as the upper high/ridge to our south-southeast retrogrades back westward into the Southern Plains. Saturday looks to bring one final days of highs in the 90s (and heat index 100+) to parts of our KS zones, but most of our CWA appears on track to have highs in the 80s both days.

- MONDAY-WEDNESDAY: Again, it's much the same, as various (mainly lower confidence) showers/thunderstorm chances persist, as our region remains under persistent west-northwesterly flow aloft, as the large- scale upper high/ridge further retrogrades back west toward NM/AZ. Odds favor highs mainly in the 80s all three days, with any 90s mainly confined to our far south in KS (as previously mentioned, am not necessarily sold on much of our CWA only reaching the 70s Monday).

AVIATION /00Z TAFS THROUGH 00Z FRIDAY/

Issued at 635 PM CDT Wed Aug 12 2026

For KGRI/KEAR Airports:

Scattered storms moving in from the west will be expected to pass through central Nebraska between mainly 5-12z. Models continue to place the outer edge of these storms near the I-80 corridor with increasing storm chances north of the interstate. The most intense and possible severe storms could move through or be in the KEAR/KGRI vicinity between mainly 5-8z. If a storms does reach the terminals in this time period as opposed to pass by to the north, gusting winds up to 60MPH could be possible.

The placement of the storms tonight could also affect the ceilings as well as visibility from fog for the night. There is high uncertainty how far south MVFR or even IFR ceilings may track south into the area. Assuming that the storms do not interfere with cloud bases, MVFR ceilings may impact either terminal site after 10z with IFR ceilings possible after 12z. Cloud bases will gradually rise back to VFR conditions between 16 and 22z.

Fog, though likely inhibited by scattered storms tonight, has a faint potential of returning between 10 and 16z. The lower confidence makes us believe that visibility reductions, if fog does form, will be more patchy than dense.

Winds speeds will mainly stay out of the northeast with steady winds between 5-15kts retaining through the night and most of the day Thursday. A few gusts as high as 25kts may be possible across the afternoon to early evening hours. Direction are also favored to become more easterly through the day Thursday. LLWS tonight between 4-11z, though the current signal looks more marginal than a given. The better LLWS chance will mainly stay southeast of the terminal sites across areas closer to the nocturnal low-level jet.

GID WATCHES/WARNINGS/ADVISORIES

NE...None. KS...Heat Advisory until 9 PM CDT this evening for KSZ005>007. Heat Advisory until 9 PM CDT Thursday for KSZ017>019.