Sioux Falls weather in May

In May, Sioux Falls sees average daytime highs of 69°F and overnight lows near 49°F, with 4.5 in of precipitation across 12.5 wet days and about 14.5 hours of daylight. It is the 5th-warmest and 2nd-wettest month of the year here.

Highs climb over the month, from about 64°F in the first days to 73°F by the end. The sky is clear or mostly clear about 27% of the time in May, and the air most often feels dry.

Daylight stretches from about 13 h 54 min at the start of May to 15 hours by month's end. Set against the rest of the year, May is Sioux Falls's 7th-clearest and 4th-windiest month. For the whole year in context, see Sioux Falls's year-round climate.

Daytime high
69°
5th warmest
Overnight low
49°
8th coldest
Precipitation
4.5 in
12.5 wet days
Daylight
14 h 30 min
5:08 AM – 7:38 PM
Cloud cover
61%
7th clearest
Wind
10 mph
4th windiest
Solar energy
5.75 kWh/m²
Travel score
5.9
out of 10

Sioux Falls is city in and seat of Minnehaha County, and largest city in South Dakota, United States.

Density
872/km²
people per km²
Founded
1856

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in May

Average highAverage lowShaded bands: 10–90% of days

Highs climb over the month, from about 64°F in the first days to 73°F by the end.

A typical May day in Sioux Falls reaches about 69°F in the afternoon and slips back to 49°F overnight — a 20°F spread between the day's warmth and the night's chill. On most days the high lands between 56°F and 81°F. Set against its neighbours, May runs about 12°F warmer than April and about 10°F cooler than June.

40°60°80°151015202531
Avg high (°F)Avg low (°F)
16342
26443
36443
46444
56544
66544
76545
86645
96646
106746
116747
126747
136847
146848
156848
166949
176949
186949
197050
207050
217051
227151
237151
247152
257252
267253
277253
287353
297354
307354
317455

How May really feels in Sioux Falls

Once humidity and wind are folded in, May averages 0 days that feel above 90°F and 0 that feel at or below 32°F — the comfort signal a plain temperature reading hides.

Days feeling ≥ 90°F
0
heat index over the day's high
Days feeling ≤ 32°F
0
wind chill below the day's low

May sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Sioux Falls weather by month

How May compares with the rest of the year at a glance. May is the 5th-warmest and 2nd-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan26° / 10°0.84.74.49.10.0
Feb31° / 13°0.94.84.410.20.0
Mar43° / 24°1.86.63.711.61.0
Apr57° / 36°3.610.32.213.24.0
May69° / 49°4.512.5014.55.9
Jun78° / 59°5.112.5015.26.4
Jul82° / 64°3.38.9014.96.5
Aug80° / 61°3.38.8013.87.0
Sep73° / 52°3.27.9012.37.2
Oct59° / 39°2.470.710.85.0
Nov43° / 25°1.65.53.19.50.9
Dec30° / 15°1.054.88.80.0

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 27% of the time in May.

Beyond those clear spells, partly cloudy skies cover about 17% of May, with mostly cloudy or overcast conditions the remaining 56%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14258
24258
34159
44159
54159
64159
74258
84357
94258
104357
114357
124357
134456
144456
154456
164456
174456
184456
194456
204555
214654
224555
234555
244654
254555
264555
274555
284753
294654
304753
314852

Chance of precipitation in May

Any precipitationSnow

Sioux Falls gets around 4.5 in of rain and snow over 12.5 wet days in May. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable precipitation averages around 41% and peaks near 43% on the wettest days.

0%10%20%30%40%50%151015202531
Rain chance (%)Snow chance (%)
1392
2391
3401
4401
5411
6411
7410
8400
9400
10400
11400
12390
13390
14390
15390
16400
17400
18400
19400
20400
21410
22410
23410
24420
25420
26420
27430
28430
29430
30430
31420

Humidity in May

DryComfortableHumidMuggyOppressiveMiserable

Most of May feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, May lands in the dry band about 80% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)
195410
294420
393520
493520
592620
692620
790730
889830
989830
1087940
11861040
12861040
13841150
14841150
15821251
16801361
17801361
18791461
19781471
20771571
21761581
22751681
23731791
24721792
257018102
267018102
276819112
286719113
296520123
306421123
316122134

Wind in May

Winds average 10 mph in May.

Across May, daily wind ranges from about 9 mph on the calmest days to 10 mph at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (mph)Feels
110light breeze
210light breeze
310light breeze
410light breeze
510light breeze
610light breeze
710light breeze
810light breeze
910light breeze
1010light breeze
1110light breeze
1210light breeze
1310light breeze
1410light breeze
1510light breeze
1610light breeze
1710light breeze
1810light breeze
1910light breeze
2010light breeze
2110light breeze
2210light breeze
2310light breeze
2410light breeze
2510light breeze
2610light breeze
2710light breeze
2810light breeze
299light breeze
309light breeze
319light breeze

Sunrise & sunset in May

DaylightNight

Daylight runs from about 13 h 54 min at the start of May to 15 hours by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 66 minutes over May. Sunrise moves from 5:27 AM to 4:55 AM, and sunset from 7:21 PM to 7:53 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
113.95:277:21
213.95:267:22
314.05:247:23
414.05:237:25
514.15:227:26
614.15:207:27
714.25:197:28
814.25:187:29
914.25:167:30
1014.35:157:32
1114.35:147:33
1214.45:137:34
1314.45:117:35
1414.45:107:36
1514.55:097:37
1614.55:087:38
1714.55:077:39
1814.65:067:40
1914.65:057:42
2014.65:047:43
2114.75:037:44
2214.75:027:45
2314.75:017:46
2414.85:007:47
2514.85:007:48
2614.84:597:49
2714.94:587:50
2814.94:577:51
2914.94:577:51
3014.94:567:52
3115.04:557:53

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 5.75 kWh/m².

For context, solar energy here swings from a low near 1.73 kWh/m² to a high of 6.67 kWh/m² in July across the year — May's 5.75 kWh/m² falls in the middle.

0246151015202531
Solar energy (kWh/m²)Level
15.5Bright
25.5Bright
35.5Bright
45.5Bright
55.5Bright
65.6Bright
75.6Bright
85.6Bright
95.6Bright
105.7Bright
115.7Bright
125.7Bright
135.7Bright
145.7Bright
155.8Bright
165.8Bright
175.8Bright
185.8Bright
195.8Bright
205.8Bright
215.8Bright
225.8Bright
235.8Bright
245.8Bright
255.9Bright
265.9Bright
275.9Bright
285.9Bright
296.0Bright
306.0Bright
316.0Intense
Planning a trip in May

Hazard calendar for Sioux Falls

In seasonPeak

In May, Sioux Falls sits inside its rainy season season. The full year is below, with each hazard's peak months called out.

Sioux Falls's rainy season runs April–October, when most of the year's rain falls.

Rainy season
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Is May a good time to visit Sioux Falls?

Our two travel scores rate May for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

5.9
Sightseeing
5th-best month of the year
3.3
Beach & pool
5th-best month of the year

May is a reasonable time to visit Sioux Falls for sightseeing.

What to pack for Sioux Falls in May

From May's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In May, Sioux Falls sees daytime highs around 69°F and nights near 49°F. Worth packing: rain gear and sun protection. About 13 days see rain.

rain gearsun protection

UV index in Sioux Falls in May

LowModerateHighVery highExtreme

Clear-sky midday UV in May peaks around 6 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Sioux Falls peaks around June 16 at about 8 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 22 at about 2 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 8 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighVery highHighModerateLowJun 16UV 8Dec 22UV 2
UV index (midday)Level
Jan2Low
Feb2Moderate
Mar4Moderate
Apr5High
May6High
Jun9Very high
Jul6High
Aug7High
Sep6High
Oct4Moderate
Nov2Moderate
Dec2Low
Location & terrain

Where is Sioux Falls?

Sioux Falls sits at 43.5°N, 96.7°W, 1,470 ft above sea level, in United States. The nearest listed city is Brookings, 53 mi away.

Topography around Sioux Falls

How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Sioux Falls.

Within 2 miles, the terrain around Sioux Falls has only modest variations in elevation — a maximum elevation change of 246 ft around an average of 1,440 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 390 ft; within 50 miles, significant variations in elevation — a maximum elevation change of 843 ft.

The land around Sioux Falls is covered by artificial surfaces (47%) and trees (37%) within 2 miles, cropland (51%) and grassland (25%) within 10 miles, and cropland (83%) within 50 miles.

2 miles
246 ft
10 miles
390 ft
50 miles
843 ft
treesgrasslandcroplandartificial surfacesbare terrainwater
May weather nearby: Brookings 53 mi · Mitchell 66 mi · Sioux City 74 mi · Watertown 96 mi · Norfolk 111 mi · Willmar 137 mi · Mankato 142 mi · Fremont 146 mi

United States travel facts

Power plugs
Type A / B
120 V · 60 Hz
Prices
≈ 100% of US
price level, 2025
GDP per capita
$90,027
2025
Happiness
6.8 / 10
World Happiness, 2025
Safe drinking water
98%
of population, 2024
Homicide rate
5.8
per 100k, 2023
Road deaths
12.7
per 100k/yr, 2019
Income group
High
World Bank
Religion
Protestant 47%unaffiliated 23%Roman Catholic 21%Jewish 2%

Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.

Data sources

Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Sioux Falls (43.5437°, -96.728°, elevation 1,470 ft), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).