Sioux Falls Pavement and Weather Data

Last reviewed 2026-07-25. Journalists, researchers, and community groups are welcome to cite any figure on this page with attribution and a link.

This page gathers the figures behind the advice on this site. Weather data are NOAA's 1991-2020 climate normals for Sioux Falls Foss Field, station USW00014944, the airport station on the north side of the city. The NOAA data service reports most values in tenths; they are converted here. The freeze-thaw count is the number of nights at or below 32 degrees minus the number of days whose high stays at or below 32.

Other figures come from the National Weather Service office in Sioux Falls, the City of Sioux Falls, the Census Bureau, USDA NRCS and the Minnehaha County comprehensive plan. Each table names its sources, and the principal ones are listed with links at the bottom of the page. Figures that could not be verified were left out rather than estimated.

Freeze-thaw by month at Foss Field

A freeze-thaw day is one when the low reaches 32 degrees or colder but the high climbs above it, so water in the pavement freezes overnight and melts the next afternoon. Foss Field averages 164.3 nights at or below freezing and 65.1 days that never thaw, which leaves about 99.2 crossing days a year. March leads every month, and October and November together add nearly 29 more before deep winter cold takes over.

June through August have no freezing nights in the normals. Monthly values are NOAA's MLY-TMIN-AVGNDS-LSTH032 and MLY-TMAX-AVGNDS-LSTH032, converted from tenths; they sum to the annual figures within rounding.

The sealing window in numbers

SealMaster's application guidance says not to seal when the temperature will fall below 50 degrees within 24 hours or when rain is due. The table shows how that rule meets Foss Field's normals. Only June, July and August have a normal low above 50, and even they average a few nights at or below it. Days with a tenth of an inch or more of precipitation peak in June, the same month the window opens.

Median last spring freeze (32F) is May 3 and median first fall freeze is September 29, a 146-day freeze-free season. In about one year in ten a 32-degree night still comes after May 19, and in about one year in ten the first one arrives before September 18.

Snow, cold and storm readings

Snow totals are moderate but spread across many days: about 32 days a year bring a tenth of an inch or more, and about 12 bring an inch or more. Deep cold drives thermal cracking, and 26 nights a year reach zero or below. Summer storms add wind and water, and the Weather Service's event summaries record several recent readings at or near the city. The state highway department notes that road salt is effective only down to about 15 degrees.

Streets, rules and growth

The city's street network frames the private work. Public Works maintains more than 900 miles of centerline streets and more than 3,500 lane miles, adds 10 to 15 miles a year, and has about 14 percent of its streets in concrete. Streets in good condition get a half-inch slurry seal of asphalt oil and small rock; worn streets get about 2 inches milled off and a new asphalt overlay. The rules below apply to private driveways and lots in the city.

Census counts and July 2025 estimates are from Census QuickFacts, except Hartford's 2020 count (2020 Census DHC table P1) and Tea's city estimate (City of Tea 2025 Development Summary). Median year built is from ACS 2020-2024 table B25035.

• Driveway approach and gutter: maintained by the property owner, per the city's overlay program notices
• Right-of-way work: Right of Way Sidewalk/Driveway Approach permit, filed online or at City Center
• Residential parking and drives: hard-surfaced with asphalt, concrete or equivalent (section 160.553)
• Commercial parking and drive areas: hard-surfaced and striped (section 160.556)
• Snow alerts: the second grader of each pair uses a snow gate; driveway snow may not go into the street
• Coal-tar sealant: no South Dakota ban on the national lists; Minnesota ban since January 1, 2014

The ground under the pavement

Soil and rock facts come from the county comprehensive plan and from NRCS. They explain why drainage and base depth decide how long local pavement lasts: silty soils feed frost heave, and the slow till beneath them keeps water close to the surface.

Sources & Methodology

Every figure above was taken from the primary sources below (accessed 2026-07-25). Where a number is derived (arithmetic on published figures) or covers a broader period or area, the text says so.

1. NOAA NCEI, 1991-2020 U.S. Climate Normals, annual and seasonal, Sioux Falls Foss Field (USW00014944) — Station name SIOUX FALLS FOSS FIELD. ANN-TMIN-AVGNDS-LSTH032 1643 (164.3 nights), ANN-TMAX-AVGNDS-LSTH032 651 (65.1 days), ANN-SNOW-NORMAL 445 (44.5 in), LSTH020 916, LSTH000 260, GRTH090 138, snow days GE010TI 123, freeze dates 05/03 and 09/29, season 146 days.
2. NOAA NCEI, 1991-2020 monthly normals: highs, lows, precipitation and snowfall — Monthly normal highs and lows in the sealing-window table and the monthly snowfall figures, in tenths.
3. NOAA NCEI, 1991-2020 monthly normals: freezing nights, frozen days, nights at or below 50F and precipitation days — Every monthly count in the freeze-thaw and sealing-window tables.
4. National Weather Service Sioux Falls, past weather events — Index to the event summaries used here: 20220512-wind-mayderecho (78 mph), 20220705-Derecho-sesdnwia (80 mph at the airport), 20220807-recordrainfall-siouxfalls (5.67 in), 20240620-22-HeavyRain-Flooding (6.70 in, 2nd highest three-day total) and 20250728-derecho (66 mph at the airport).
5. City of Sioux Falls Public Works, Streets division — More than 900 centerline miles, 10 to 15 miles added each year, about 14 percent concrete. Lane miles from the Public Works department page.
6. City of Sioux Falls, asphalt overlay program — Milling of about 2 inches before overlay, and the statement that the driveway approach and associated gutter are the property owner's responsibility.
7. U.S. Census Bureau QuickFacts, Sioux Falls city — 2010 and 2020 counts and the July 2025 estimate for Sioux Falls; the other towns' figures come from their own QuickFacts pages, and median year built from ACS table B25035 at data.census.gov.
8. Minnehaha County, Envision 2045 Comprehensive Plan — Loess over glacial till in the eastern two-thirds of the county, Sioux quartzite bedrock near the surface in the eastern half, four working stone quarries, sand and gravel along river and stream beds.
9. USDA NRCS Official Soil Series Description, Egan series — Silty sediment 25 to 40 inches over loam or clay loam till, moderate over moderately slow or slow permeability, 25 to 35 percent clay, large extent in east-central and southeastern South Dakota.