Watertown weather in May

In May, Watertown sees average daytime highs of 66°F and overnight lows near 46°F, with 3.4 in of precipitation across 11.4 wet days and about 14.6 hours of daylight. It is the 5th-warmest and 2nd-wettest month of the year here.

Highs climb over the month, from about 61°F in the first days to 70°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 14 hours at the start of May to 15 h 06 min by month's end. Set against the rest of the year, May is Watertown's 7th-clearest and 8th-windiest month. For the whole year in context, see Watertown's year-round climate.

Daytime high
66°
5th warmest
Overnight low
46°
8th coldest
Precipitation
3.4 in
11.4 wet days
Daylight
14 h 36 min
5:06 AM – 7:44 PM
Cloud cover
62%
7th clearest
Wind
10 mph
8th windiest
Solar energy
5.82 kWh/m²
Travel score
5.7
out of 10

Watertown is city in and county seat of Codington County, South Dakota, United States.

Density
329/km²
people per km²
Founded
1879

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 61°F in the first days to 70°F by the end.

A typical May day in Watertown reaches about 66°F in the afternoon and slips back to 46°F overnight — a 20°F spread between the day's warmth and the night's chill. On most days the high lands between 52°F and 79°F. Set against its neighbours, May runs about 13°F warmer than April and about 10°F cooler than June.

20°40°60°80°151015202531
Avg high (°F)Avg low (°F)
16040
26040
36141
46141
56142
66242
76242
86343
96343
106444
116444
126444
136545
146545
156546
166646
176647
186747
196747
206748
216848
226849
236849
246949
256950
266950
277051
287051
297051
307152
317152

How May really feels in Watertown

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.

Watertown 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
Jan21° / 0.95.25.490.0
Feb25° / 10°0.84.64.610.10.0
Mar38° / 21°1.663.811.60.2
Apr53° / 33°2.89.5313.23.0
May66° / 46°3.411.40.114.65.7
Jun75° / 57°4.412.2015.36.5
Jul80° / 62°3.19.4015.16.9
Aug78° / 59°3.29.3013.97.1
Sep71° / 50°2.58012.37.0
Oct56° / 37°2.26.91.210.74.1
Nov40° / 24°1.353.69.40.4
Dec26° / 13°0.955.48.70.0

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 15% of May, with mostly cloudy or overcast conditions the remaining 58%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14357
24357
34357
44357
54357
64357
74357
84357
94357
104456
114456
124456
134357
144357
154357
164357
174357
184258
194258
204258
214258
224258
234060
244060
254060
264060
274060
284060
294159
304159
314159

Chance of precipitation in May

Any precipitationSnow

Watertown gets around 3.4 in of rain and snow over 11.4 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 37% and peaks near 40% on the wettest days, and about 0 day brings snow.

0%10%20%30%40%50%151015202531
Rain chance (%)Snow chance (%)
1343
2353
3353
4362
5362
6362
7361
8371
9371
10371
11371
12370
13370
14370
15370
16370
17370
18370
19370
20370
21370
22370
23370
24380
25380
26380
27390
28390
29390
30400
31400

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 88% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)
198200
297300
397300
496400
596400
695410
794510
894510
993610
1093610
1191720
1291720
1391720
1490820
1589830
1689830
1788930
1888930
19861040
20861040
21851140
22851140
23831250
24831250
25821350
26811360
27801460
28781561
29771571
30761671
31741781

Wind in May

Winds average 10 mph in May.

Across May, daily wind ranges from about 10 mph on the calmest days to 11 mph at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (mph)Feels
110light breeze
211light breeze
311light breeze
411light breeze
511light breeze
611light breeze
711light breeze
811light breeze
911light breeze
1011light breeze
1111light breeze
1211light breeze
1311light breeze
1411light breeze
1511light breeze
1611light breeze
1711light breeze
1810light breeze
1910light breeze
2010light breeze
2110light breeze
2210light breeze
2310light breeze
2410light breeze
2510light breeze
2610light breeze
2710light breeze
2810light breeze
2910light breeze
3010light breeze
3110light breeze

Sunrise & sunset in May

DaylightNight

Daylight runs from about 14 hours at the start of May to 15 h 06 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 66 minutes over May. Sunrise moves from 5:26 AM to 4:52 AM, and sunset from 7:25 PM to 7:59 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
114.05:267:25
214.05:247:27
314.15:237:28
414.15:217:29
514.25:207:30
614.25:197:32
714.35:177:33
814.35:167:34
914.35:147:35
1014.45:137:37
1114.45:127:38
1214.55:117:39
1314.55:097:40
1414.65:087:41
1514.65:077:43
1614.65:067:44
1714.75:057:45
1814.75:047:46
1914.75:027:47
2014.85:017:48
2114.85:007:49
2214.84:597:50
2314.94:597:51
2414.94:587:52
2514.94:577:54
2615.04:567:55
2715.04:557:56
2815.04:547:57
2915.14:547:57
3015.14:537:58
3115.14:527:59

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 5.82 kWh/m².

For context, solar energy here swings from a low near 1.56 kWh/m² to a high of 6.64 kWh/m² in July across the year — May's 5.82 kWh/m² sits near the top of that range.

0246151015202531
Solar energy (kWh/m²)Level
15.6Bright
25.6Bright
35.6Bright
45.6Bright
55.6Bright
65.6Bright
75.7Bright
85.7Bright
95.7Bright
105.7Bright
115.7Bright
125.8Bright
135.8Bright
145.8Bright
155.8Bright
165.8Bright
175.9Bright
185.9Bright
195.9Bright
205.9Bright
215.9Bright
225.9Bright
235.9Bright
245.9Bright
255.9Bright
266.0Bright
276.0Bright
286.0Bright
296.0Intense
306.0Intense
316.0Intense
Planning a trip in May

Hazard calendar for Watertown

In seasonPeak

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

Watertown sits in the Atlantic hurricane belt; the season peaks August–October.

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

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

Is May a good time to visit Watertown?

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

5.7
Sightseeing
5th-best month of the year
2.3
Beach & pool
5th-best month of the year

May is a reasonable time to visit Watertown for sightseeing.

What to pack for Watertown in May

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

In May, Watertown sees daytime highs around 66°F and nights near 46°F. Worth packing: a warm layer, rain gear and sun protection. About 11 days see rain.

a warm layerrain gearsun protection

UV index in Watertown 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 Watertown peaks around June 19 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near January 1 at about 1 (low).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighVery highHighModerateLowJun 19UV 9Jan 1UV 1
UV index (midday)Level
Jan1Low
Feb2Moderate
Mar4Moderate
Apr5Moderate
May6High
Jun9Very high
Jul8Very high
Aug6High
Sep6High
Oct4Moderate
Nov2Low
Dec1Low
Location & terrain

Where is Watertown?

Watertown sits at 44.9°N, 97.1°W, 1,732 ft above sea level, in United States. The nearest listed city is Brookings, 43 mi away.

Topography around Watertown

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

Within 2 miles, the terrain around Watertown has only modest variations in elevation — a maximum elevation change of 115 ft around an average of 1,736 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 344 ft; within 50 miles, significant variations in elevation — a maximum elevation change of 1,237 ft.

The land around Watertown is covered by grassland (38%) and artificial surfaces (29%) within 2 miles, cropland (58%) and grassland (28%) within 10 miles, and cropland (62%) and grassland (29%) within 50 miles.

2 miles
115 ft
10 miles
344 ft
50 miles
1,237 ft
treesgrasslandcroplandartificial surfacesbare terrainwater
May weather nearby: Brookings 43 mi · Aberdeen 78 mi · Mitchell 94 mi · Sioux Falls 96 mi · Willmar 103 mi · West Fargo 137 mi · Moorhead 137 mi · Fargo 137 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 Watertown (44.8994°, -97.1151°, elevation 1,732 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. Tropical-cyclone seasons are the published climatological basin seasons (NOAA National Hurricane Center / regional warning centres). 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).