Watertown weather in August

In August, Watertown sees average daytime highs of 78°F and overnight lows near 59°F, with 3.2 in of rain across 9.3 wet days and about 13.9 hours of daylight. It is the 2nd-warmest and 3rd-wettest month of the year here.

Day-to-day highs hold fairly steady near 78°F through the month. The sky is clear or mostly clear about 47% of the time in August, and the air most often feels humid.

Daylight stretches from about 14 h 36 min at the start of August to 13 h 12 min by month's end. Set against the rest of the year, August is Watertown's 2nd-clearest and 11th-windiest month. For the whole year in context, see Watertown's year-round climate.

Daytime high
78°
2nd warmest
Overnight low
59°
11th coldest
Rainfall
3.2 in
9.3 wet days
Daylight
13 h 54 min
5:36 AM – 7:29 PM
Cloud cover
45%
2nd clearest
Wind
9 mph
11th windiest
Solar energy
5.75 kWh/m²
Travel score
7.1
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 August

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 78°F through the month.

A typical August day in Watertown reaches about 78°F in the afternoon and slips back to 59°F overnight — a 19°F spread between the day's warmth and the night's chill. On most days the high lands between 70°F and 87°F. Set against its neighbours, August runs about 2°F cooler than July and about 8°F warmer than September.

40°60°80°151015202531
Avg high (°F)Avg low (°F)
18061
28061
38060
47960
57960
67960
77960
87960
97960
107960
117960
127859
137859
147859
157859
167859
177859
187859
197859
207859
217858
227858
237858
247858
257858
267858
277858
287758
297757
307757
317757

How August really feels in Watertown

Once humidity and wind are folded in, August 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

August 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 August compares with the rest of the year at a glance. August is the 2nd-warmest and 3rd-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 August

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 47% of the time in August.

Beyond those clear spells, partly cloudy skies cover about 19% of August, with mostly cloudy or overcast conditions the remaining 34%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
16931
26832
36832
46733
56733
66634
76535
86535
96436
106436
116436
126436
136535
146535
156535
166535
176535
186535
196634
206634
216733
226634
236634
246733
256733
266733
276733
286733
296733
306733
316733

Chance of precipitation in August

Any precipitation

Watertown gets around 3.2 in of rain over 9.3 wet days in August. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 30% and peaks near 31% on the wettest days.

0%10%20%30%40%151015202531
Rain chance (%)
131
231
331
431
531
631
731
831
931
1031
1131
1231
1331
1431
1531
1631
1731
1831
1930
2030
2130
2230
2329
2429
2528
2627
2727
2827
2926
3026
3126

Humidity in August

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, August lands in the humid band about 28% of days. Sticky, muggy-or-worse air turns up on roughly 18% of them.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1222926185
2222826185
3222827184
4222827184
5222827184
6222828184
7232828184
8232828173
9232828173
10232829173
11242829163
12242829163
13252829153
14252829152
15262829152
16262829152
17272729162
18272729161
19282729161
20282629161
21292628161
22292528161
23302528161
24312428161
25322428161
26332427161
27342327151
28352326151
29372226140
30392225130
31412224120

Wind in August

Winds average 9 mph in August.

Across August, daily wind ranges from about 8 mph on the calmest days to 10 mph at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (mph)Feels
18light breeze
28light breeze
38light breeze
48light breeze
58light breeze
68light breeze
78light breeze
88light breeze
98light breeze
108light breeze
118light breeze
128light breeze
138light breeze
149light breeze
159light breeze
169light breeze
179light breeze
189light breeze
199light breeze
209light breeze
219light breeze
229light breeze
239light breeze
249light breeze
259light breeze
269light breeze
279light breeze
289light breeze
299light breeze
3010light breeze
3110light breeze

Sunrise & sunset in August

DaylightNight

Daylight runs from about 14 h 36 min at the start of August to 13 h 12 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 84 minutes over August. Sunrise moves from 5:18 AM to 5:54 AM, and sunset from 7:51 PM to 7:03 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
114.65:187:51
214.55:197:50
314.55:207:49
414.45:217:47
514.45:227:46
614.35:247:45
714.35:257:43
814.35:267:42
914.25:277:40
1014.25:287:39
1114.15:307:37
1214.15:317:36
1314.05:327:34
1414.05:337:33
1513.95:347:31
1613.95:367:29
1713.95:377:28
1813.85:387:26
1913.85:397:25
2013.75:407:23
2113.75:427:21
2213.65:437:19
2313.65:447:18
2413.55:457:16
2513.55:477:14
2613.45:487:12
2713.45:497:10
2813.35:507:09
2913.35:517:07
3013.25:537:05
3113.25:547:03

Solar energy in August

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in August, about 5.75 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 — August's 5.75 kWh/m² falls in the middle.

0246151015202531
Solar energy (kWh/m²)Level
16.2Intense
26.2Intense
36.2Intense
46.1Intense
56.1Intense
66.0Intense
76.0Intense
86.0Bright
95.9Bright
105.9Bright
115.9Bright
125.8Bright
135.8Bright
145.8Bright
155.8Bright
165.8Bright
175.7Bright
185.7Bright
195.7Bright
205.7Bright
215.6Bright
225.6Bright
235.6Bright
245.5Bright
255.5Bright
265.5Bright
275.4Bright
285.4Bright
295.3Bright
305.3Bright
315.3Bright
Planning a trip in August

Hazard calendar for Watertown

In seasonPeak

In August, Watertown sits inside its atlantic hurricane and 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 August a good time to visit Watertown?

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

7.1
Sightseeing
1st-best month of the year
6.7
Beach & pool
2nd-best month of the year

August is one of the better times to visit Watertown for general sightseeing. The water and warmth also suit a beach or pool day.

What to pack for Watertown in August

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

In August, Watertown sees daytime highs around 78°F and nights near 59°F. Worth packing: light clothes, rain gear and sun protection. About 9 days see rain.

light clothesrain gearsun protection

UV index in Watertown in August

LowModerateHighVery highExtreme

Clear-sky midday UV in August 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
August 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).