textproduct: Aberdeen

KEY MESSAGES

- High temperatures today will be in the upper 90s to low 100s over central and north central South Dakota. Heat index values up to 102 will be possible. A Heat Advisory is in effect from 12 PM CDT through 8 PM CDT today for that area.

- Western wildfire smoke may impact visibility at times across the region through this evening. Smoke may drop air quality to the point of impacting those sensitive to smoke.

- A Marginal Risk (level 1 of 5) for severe weather is in place over parts north central South Dakota west of the Missouri River this evening. Wind gusts of 60 miles per hour will be the main severe threat.

- A Marginal Risk (level 1 of 5) for severe weather is in place Thursday. The main hazard will be wind gusts of 60 mph and hail of one inch in diameter.

DISCUSSION

Issued at 245 AM CDT Wed Jul 29 2026

Main forecast focus today is the continuation of abnormal heat thanks to a broad upper-level ridge allowing a warm airmass into the region. Over central and north central South Dakota specifically, heat index values will top out over 100 degrees this afternoon, and Heat Risk will reach the Major category in some places. With these factors in mind, a Heat Advisory has been issued for this afternoon over central and north central South Dakota. Admittedly parts of the area under the advisory are a bit borderline and/or spotty for reaching Heat Advisory criteria of 100 degree apparent temperatures. One potential failure point for temperatures today will be the addition of smoke across the region originating from wildfires in the Pacific Northwest. Smoke is mainly expected to remain aloft (still having an impact on temperatures), although some near-surface smoke remains possible. Concentrations at the surface may cause some minor visibility reductions and push air quality up to Moderate levels (which corresponds to Air Quality Index values of 50-100). This level of air quality means that mainly those sensitive to smoke will be impacted.

Beginning this evening into tonight, a severe weather threat will emerge over parts of north central South Dakota, mainly west of the Missouri River. The latest high-resolution guidance keeps most of the storms to the west until the late evening to early overnight hours. By the time storms reach the Aberdeen CWA, they will encounter an environment that will not be particularly supportive of storms. A lack of strong shear (<30 knots) and CAPE of around 1000 J/kg will likely struggle to maintain storms, and storms that make it may dissipate shortly after crossing the CWA border. Naturally with collapsing storms, wind will be the main severe threat. DCAPE values in particular will be quite high, with high-res model guidance resolving upwards of 1500 J/kg over the area. Fairly strong low-level lapse rates (Near-dry adiabatic lapse rates all the way up to roughly 5-6 km in model soundings) may also be present, allowing for easy access to the surface. Diurnal cooling may temper these strong lapse rates depending on when storms arrive over the area, but the threat likely remains. A Marginal Risk is in place to cover this threat.

Showers and storms will continue from Wednesday night into Thursday morning, spreading eastward throughout the morning hours. While severe weather during that morning period can't entirely be ruled out, chances for severe weather increase in the Thursday afternoon to evening period. Wind will once again be a threat, although perhaps under a less impressive DCAPE environment than on Wednesday. The persistent cloud cover will also limit the diurnal heating and subsequently low-level lapse rates. Hail is also a possible threat, but storms will again be dealing with shear up to roughly 30 knots, which may make it difficult. MUCAPE values do reach around 2000 J/kg however, so that will be one thing working in favor of storm development and maintenance. Another Marginal Risk is in place Thursday, this time covering the entire Aberdeen CWA.

As the shortwave influence exits the region, it will begin to deepen over the eastern CONUS. The upper-level ridge will therefore become more positively tilted, still allowing for a warm airmass to sit overhead. The presence of the trough to the east may create a bit of a gradient in temperatures over the forecast region however. This will likely result in near-normal temperatures (mid-80s) over northeastern South Dakota and western Minnesota and above normal temperatures (90s) over central and north central South Dakota. Ensembles then show the potential for an upper-level trough to move through early next week, with the base of the trough located over the Northern Plains. This may provide the next chances for rain over the area, although at this time range it is difficult to pinpoint exactly. Currently confidence is highest in precipitation to the north of the CWA in North Dakota based on the location of the jet streak in ensemble forecasts, but it will likely dip far enough south to support some development south of the state line as well.

AVIATION /06Z TAFS THROUGH 06Z THURSDAY/

Issued at 1227 AM CDT Wed Jul 29 2026

Terminals KABR,KATY,KPIR,KMBG

Expect VFR conditions through the next 24 hours. The main concern will be near surface smoke dropping visibility to 6SM at times. At 05Z all of the air quality reporting platforms were in the Moderate (yellow) category across the forecast area.

ABR WATCHES/WARNINGS/ADVISORIES

SD...Heat Advisory from noon CDT /11 AM MDT/ today to 8 PM CDT /7 PM MDT/ this evening for SDZ003-004-009-015-016-033>037- 045-048-051. MN...None.