textproduct: Hastings

KEY MESSAGES

- Another evening of severe weather will be possible again today. Storms will be capable of producing large hail, damaging winds and even potentially a tornado.

- The best storm potential will be concentrated areas areas near and east of HWY-281 between 4-11PM.

- Critical fire weather conditions are expected to arise across a few southwest portions of the area. Gusty southerly winds as high as 35-40MPH will overlap with dry conditions (RH values as low as 10- 20%). A Red Flag Warning is in effect from 1-9PM for counties south of Harlan and Franklin counties.

- Severe weather is possible to return Monday evening for a few locations mainly southeast of the Tri-Cities.

- Highs, following the passage of a cold front Monday, will drop down to primarily the 60s for Tuesday/Wednesday/Thursday, the 70s for Friday and the upper 70s to low 80s for Saturday.

UPDATE

Issued at 351 AM CDT Sun May 17 2026

Today...

The active pattern continues on today as a negatively tilted upper- level trough digs into the Central Plains. Height falls at the surface, forced by CVA along the exit region of the trough, has led to the strengthening of a surface cyclone centered over Western Kansas/Nebraska this morning. This low should continue to take a northeastward trajectory, lifting a warm front up and through the area with a trailing dryline punching in behind. This dryline will not only serve as a storm lifting mechanism, but as a demarcation of the very dry airmass that is set to stir fire weather concerns for a few southwest portions of the area. A Red Flag Warning will be in effect from 1PM to 9PM as gusty southerly winds (gusting as high as 35-40MPH) mix with this very dry airmass (RH values as low as 10- 15%) for counties south of Harlan and Franklin counties. For more information regarding the fire weather potential for the week, please refer to the Fire Weather section below.

Ahead of this dryline, warm, moist and unstable air should seep back into much of south central to southeast Nebraska, priming the afternoon for yet another evening of severe weather. Given the highly unstable environment (3,000-4,000J/km MUCAPE), sufficient shear (30- 45kts BWD) and ample moisture (mid to upper 50s dewpoints), any storm that manages to fire this afternoon/evening will easily have the potential to become severe. The main concerns would be damaging thunderstorm wind gusts up to 70 MPH with large hail up to the size of baseballs. An isolated tornado can also not be fully counted out, though the linear forcing mechanism may favor a squall line storm mode over discrete supercells.

The latest high resolution model guidance (HRRR & NAMNEST), both highlight a line of storms zipping down the dryline as it crosses through central Nebraska between 4-11PM. The main uncertainty that has not been consistently handled across the model trends thus far has been when and where these storms initially fire. The timing for when storms develop and how far the dryline advances through the day, will ultimately determine where the severe weather threat end up. Generally speaking, the better potential for severe weather will be concentrated to locations near and east of HWY-281. If storms, however, snap earlier than the models currently suggest, a few severe storms could manage to pop up just west of HWY-281.

Given the prime thunderstorm ingredients establishing across the area, the SPC has included most of the area underneath an enhanced severe weather outlook (level 3 of 5). In reality, the majority of the action should take place across the eastern half of the area (locations found ahead of the eastward advancing dryline.

Monday...

Severe weather concerns will once again be expected to return to a southeast portion of the area Monday afternoon to evening. A cold front powering through the area during the day, will drop highs from the upper 80s and 90s Sunday down to the 50s and 60s for northeast portions of the area and down to the 70s and 80s for the southeast half of the area (locations where the front reaches later in the day). The front will also be responsible for initiating a line of severe storms between 3-5PM. The latest CAM guidance keeps the convection bound to only a few of our far southeastern locations (mainly to Mitchell, Jewell, Thayer and Fillmore counties.) The SPC keeps only our southeast half under a severe weather outlook with the highest risk (enhanced level 3 out of 5) southeast of a line from Beloit, KS to Friend, NE.

DISCUSSION

Issued at 327 PM CDT Sat May 16 2026

Short discussion here as we transition to severe weather ops.

Two main convective regimes for the short term: 1) isolated supercells along a retreating warm front over mainly south central Nebraska late this afternoon and evening. All modes of severe will be possible given potent combination of instability and shear. Already seeing signs of this along I-80 corridor.

2) larger complex of storms is forecast to move in from the W later this evening. This activity would have an organized with threat with it, as well as potential for QLCS tornadoes. This is concerning considering the late time of day and difficult to spot them. Could also see some large hail, but would be a secondary threat. Can't rule out a few swaths of wind driven hail. Isolated gusts up to 80 MPH will be possible in the strongest cores. This batch favors south central Nebraska more than Kansas, but KS zones by no means in the clear.

Severe threat should end by around 09Z.

Focus then turns to Sunday's severe weather and fire weather potential. Will all depend on where the dry line sets up, but trends have been to shift this further E and bring more of the dry surge and fire weather into play. Will need to seem how things settle from today...but anywhere along and ahead of the dry line could see significant severe weather, including intense supercells with very large hail, damaging wind gusts, and tornadoes. The greatest tornado threat looks to be along and E/NE of the Hwy 81 corridor. Late afternoon and early evening is the main time frame of concern for dry line storms. Another batch of severe storms with mainly a large hail and wind threat could move in from the NW along the primary cold front late Sunday evening and into the overnight.

Fire weather discussion will be included below shortly.

Exactly how things unfold Sunday will determine frontal location for Monday. As mentioned above, this is trending further E/SE such that most of out area could be on the cool side of the front by midday. In fact, far N/NW zones could struggle to get out of the 50s while far S/SE zones push 90F. A strong spring front, indeed, that is bound to spark off widespread severe weather...just a question of if it's here or just E/SE.

Not much time spent in the extended periods as it appears fairly quiet.

AVIATION /12Z TAFS THROUGH 12Z MONDAY/

Issued at 641 AM CDT Sun May 17 2026

For KGRI/KEAR Airports:

The MVFR ceiling to not become as widespread as originally expected this morning. Instead bases have seemed to hover near 4-8kft. Broken to overcast skies will likely maintain through most of the day (beyond a brief 17-22z period). Unless an afternoon thunderstorm approaches the KEAR vicinity between 23-2z, MVFR ceiling are not expected to return for the rest of the 12z TAF period.

Winds today will remain fairly stable through 19z. Southerly winds picking up this morning will mainly blow between 15-25kts today with gusts as high as 30-40kts. Between 19-0z, wind directions will flip from a southerly to northerly direction with the passing of a dryline. Winds are not expected to let up after becoming northerly (15-20kts sustained with gusts as high as 25-35kts). Wind speeds will not decelerate until closer to 6z.

FIRE WEATHER

Issued at 351 AM CDT Sun May 17 2026

A deepening surface low across western Kansas and Nebraska today will activate fairly gusty southerly winds. Wind speeds will pick up this morning, blowing between 15-25MPH with gusts as high as 35-40MPH possible through the evening. Highs peaking in the mid to upper 90s across a few far southern Nebraska and north central Kansas areas, with the dryline later dropping dewpoints from the 50s to 40s, will quickly help dry conditions out. RH values as result will tank as low as 10-20% across much of north central Nebraska and for the far southern row of Nebraska counties.

Despite the moisture that was deposited from last night thunderstorms, the dry afternoon punch will easily dry conditions back down to critical concerns. A Red Flag Warning will be in effect from 1-9PM for Harlan and Franklin counties in Nebraska and for Phillips, Smith, Rooks and Osborne counties in Kansas. A few areas of near-critical fire weather conditions may still be observed across a few of our Kansas areas or far southern Nebraska areas outside of the warning.

GID WATCHES/WARNINGS/ADVISORIES

NE...Red Flag Warning from 1 PM this afternoon to 9 PM CDT this evening for NEZ083-084. KS...Red Flag Warning from 1 PM this afternoon to 9 PM CDT this evening for KSZ005-006-017-018.