textproduct: Aberdeen

KEY MESSAGES

- A Marginal Risk (Level 1 of 5) is in place for storms developing Monday afternoon and evening. The main severe threats during that time frame will be hail of 1 inch in diameter and wind gusts of 60 miles per hour.

- Chances for severe storms return on Tuesday, and a Slight Risk (Level 2 of 5) for much of the forecast area. All severe threats, including wind of 60 to 70 miles per hour, hail of 1 inch in diameter, tornadoes, and heavy rainfall leading to flash flooding.

- Temperatures roughly 5 to 10 degrees above normal (highs in the upper 80s to low 90s) are expected through Tuesday. Temperatures are expected to cool slightly to highs in the low to mid 80s beginning Wednesday.

UPDATE

Issued at 639 AM CDT Sun Jul 5 2026

See below for an aviation forecast discussion for the 12Z TAFs.

DISCUSSION

Issued at 257 AM CDT Sun Jul 5 2026

A much needed break from thunderstorms today with a dry forecast in place. Main forecast concern is the potential for fog to develop once again this morning near sunrise. Fog development will be possible due to light and variable winds as well as clear skies, with the best chances over northeastern South Dakota and western Minnesota, as well as along the James River Valley (albeit to a lesser extent than other areas). Visibility may drop below a mile at times, and can't quite rule out the possibility of a Dense Fog Advisory this morning depending on how things play out. Dew point depressions are already (as of the 06Z observations) less than three degrees in many places over northeastern South Dakota and western Minnesota. Otherwise, expect more of the same today in terms of high temperatures 5-10 degrees above normal (into the 90s across the region). Some slightly stronger southeasterly winds gusting up to 25 to 35 miles per hour will arrive along and west of the Missouri River in the afternoon, and will continue overnight tonight.

Development along a cold front Monday will bring about the return of the severe weather potential across the region. Main severe concern at this time is the wind potential, with strong low-level lapse rates (>8 C/km) and DCAPE > 1000 J/kg in place. Early looks at CAMs are also signaling the potential for storms to evolve into a QLCS storm mode by the time they make their way into the Aberdeen forecast area, which further supports the wind potential. Hail may be a secondary concern, as ample CAPE (potentially upwards of 2000 J/kg) and mid-level lapse rates around 7 C/km will be in place. A lack of shear may be a problem, but given how recent similar setups have played out, this may not be a barrier to severe hail. Not anticipating favorable conditions for tornado development at this time, mainly given the very high LCLs in the area.

Another round of severe weather will be possible on Tuesday. The aforementioned front is expected to settle in over the region and become stationary, and convection appears possible during the daytime along that front, mainly over northeastern South Dakota. Increased chances for rain arrive during the evening to overnight period Tuesday into Wednesday, over 80% PoPs over the entire forecast area. At this point, it appears that a fairly favorable CAPE/Shear environment will be in place to sustain a hail threat, particularly during the afternoon time frame Tuesday where 700-500 lapse rates are the strongest. The wind threat will likely remain contingent on exactly where the boundary sets up. Due to capping from the front, low-level lapse rates north of the boundary will be quite poor and gusts will have difficulty reaching the surface. Areas to the south (in the warm sector) will have a bit better conditions for wind due to the stronger low-level lapse rates. Tornadoes also appear possible Tuesday, supported by a combination of widespread 0-3km helicity upwards of 200 m2/s2, LCLs generally 1000m or less, and pockets of low-level wind shear upwards of 25 knots. Confidence remains fairly low still, but worth keeping an eye on as it approaches. Flash flooding due to excessive rainfall will also be a threat, and a Slight Risk ERO is in place in addition to the Slight severe weather outlook. Looking at the latest NBM 24 hour QPF through Wednesday morning, 90th percentile values (which would be more in line with thunderstorms tracking over the region) sit around 3-3.5" at peak over far northeastern South Dakota and western Minnesota, which at this time range warrants a closer look at the potential moving forward. Luckily, soil saturation in that area remains fairly low at this time The caveat to that is that Monday's storms may track over the same area, so we may not be able to rely on those dry soils to abate some of the potential threat.

Extended severe weather risk models also highlight potential for severe storms Wednesday and Thursday, albeit to a lesser extent than Tuesday. Outside of severe chances, expect temperatures to remain in the upper 80s to low 90s through at least the start of the week. By the middle of the week, indications are that the upper-level pattern will transition to near-zonal flow over the Northern Plains, which will facilitate a slight cooldown to near-normal (highs in the mid 80s).

AVIATION /12Z TAFS THROUGH 12Z MONDAY/

Issued at 639 AM CDT Sun Jul 5 2026

Terminals KABR,KATY,KPIR,KMBG

After some morning ground fog (sub-VFR), all four terminals are forecast to experience good VFR conditions throughout the TAF valid period.

ABR WATCHES/WARNINGS/ADVISORIES

SD...None. MN...None.