Watertown weather in May

In May, Watertown sees average daytime highs of 67°F and overnight lows near 49°F, with 3.7 in of rain across 11.8 wet days and about 14.4 hours of daylight. It is the 5th-warmest and 2nd-wettest month of the year here.

Highs climb over the month, from about 62°F in the first days to 72°F by the end. The sky is clear or mostly clear about 24% 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 14 h 54 min by month's end. Set against the rest of the year, May is Watertown's 6th-clearest and 8th-windiest month. For the whole year in context, see Watertown's year-round climate.

Daytime high
67°
5th warmest
Overnight low
49°
8th coldest
Rainfall
3.7 in
11.8 wet days
Daylight
14 h 30 min
4:37 AM – 7:05 PM
Cloud cover
65%
6th clearest
Wind
8 mph
8th windiest
Solar energy
5.74 kWh/m²
Travel score
5.8
out of 10

Watertown is city in Dodge County and Jefferson County, Wisconsin, United States.

Density
739/km²
people per km²

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 62°F in the first days to 72°F by the end.

A typical May day in Watertown reaches about 67°F in the afternoon and slips back to 49°F overnight — a 19°F spread between the day's warmth and the night's chill. On most days the high lands between 55°F and 80°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)
16243
26244
36244
46344
56345
66445
76446
86446
96546
106547
116547
126647
136647
146748
156748
166748
176849
186849
196849
206950
216950
226951
237051
247051
257152
267152
277153
287253
297253
307254
317354

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
Jan27° / 13°1.67.96.69.20.0
Feb31° / 16°1.66.95.510.20.0
Mar43° / 26°2.38.93.911.60.8
Apr56° / 38°3.712.11.913.13.5
May67° / 49°3.711.8014.45.8
Jun77° / 59°3.911.2015.16.6
Jul81° / 63°3.29.9014.96.6
Aug79° / 61°3.510.2013.86.8
Sep72° / 53°2.98.8012.36.9
Oct58° / 42°2.890.310.84.5
Nov44° / 30°2.17.929.50.9
Dec32° / 20°1.97.65.48.90.0

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 24% 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 59%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
13961
23862
33862
43862
53862
63763
73763
83862
93862
103862
113862
123961
134060
144060
154060
164159
174159
184159
194258
204258
214357
224357
234357
244456
254456
264456
274456
284456
294456
304456
314456

Chance of precipitation in May

Any precipitation

Watertown gets around 3.7 in of rain over 11.8 wet days in May. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 38% and peaks near 40% on the wettest days.

0%10%20%30%40%50%151015202531
Rain chance (%)
139
239
339
439
539
639
739
839
940
1040
1140
1240
1339
1439
1539
1639
1738
1838
1938
2037
2137
2237
2337
2437
2537
2637
2737
2837
2937
3037
3137

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 81% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)
194510
294510
392620
492620
592620
690730
790730
889740
989740
1088750
1188750
1286761
1385861
1485861
1584871
1684871
1784871
1881982
1981982
2079993
21781093
22771094
237511104
247412104
257213105
267114105
277014105
286815116
296716116
306617116
316518116

Wind in May

Winds average 8 mph in May.

Across May, daily wind ranges from about 8 mph on the calmest days to 9 mph at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (mph)Feels
19light breeze
29light breeze
39light breeze
49light breeze
59light breeze
69light breeze
78light breeze
88light breeze
98light breeze
108light breeze
118light breeze
128light breeze
138light breeze
148light breeze
158light breeze
168light breeze
178light breeze
188light breeze
198light breeze
208light breeze
218light breeze
228light breeze
238light breeze
248light breeze
258light breeze
268light breeze
278light breeze
288light breeze
298light breeze
308light breeze
318light breeze

Sunrise & sunset in May

DaylightNight

Daylight runs from about 13 h 54 min at the start of May to 14 h 54 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 60 minutes over May. Sunrise moves from 4:56 AM to 4:25 AM, and sunset from 6:48 PM to 7:20 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
113.94:566:48
213.94:546:50
314.04:536:51
414.04:526:52
514.04:506:53
614.14:496:54
714.14:486:55
814.24:466:56
914.24:456:58
1014.24:446:59
1114.34:437:00
1214.34:417:01
1314.44:407:02
1414.44:397:03
1514.44:387:04
1614.54:377:05
1714.54:367:06
1814.54:357:08
1914.64:347:09
2014.64:337:10
2114.64:327:11
2214.74:317:12
2314.74:307:13
2414.74:297:14
2514.84:297:15
2614.84:287:16
2714.84:277:17
2814.94:267:17
2914.94:267:18
3014.94:257:19
3114.94:257:20

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 5.74 kWh/m².

For context, solar energy here swings from a low near 1.54 kWh/m² to a high of 6.3 kWh/m² in June across the year — May's 5.74 kWh/m² sits near the top of that range.

0246151015202531
Solar energy (kWh/m²)Level
15.3Bright
25.4Bright
35.4Bright
45.4Bright
55.4Bright
65.4Bright
75.5Bright
85.5Bright
95.5Bright
105.5Bright
115.6Bright
125.6Bright
135.7Bright
145.7Bright
155.7Bright
165.8Bright
175.8Bright
185.8Bright
195.9Bright
205.9Bright
215.9Bright
225.9Bright
236.0Bright
246.0Bright
256.0Intense
266.0Intense
276.0Intense
286.0Intense
296.1Intense
306.1Intense
316.1Intense
Planning a trip in May

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).

5.8
Sightseeing
5th-best month of the year
2.9
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 67°F and nights near 49°F. Worth packing: rain gear and sun protection. About 12 days see rain.

rain gearsun protection

Sea temperature near Watertown in May

The nearest coast averages about 42°F in May — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 44 mi away) is warmest in August at about 70°F and coldest in March near 36°F.

It's comfortable for a long swim from Jul 29 to Aug 30 — about 1.1 months when the water holds above 68°F.

30°40°50°60°70°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarm
Sea temperature (°F)Comfort
Jan38Bracing
Feb36Bracing
Mar36Bracing
Apr38Bracing
May42Bracing
Jun54Bracing
Jul67Cool
Aug70Refreshing
Sep66Cool
Oct56Bracing
Nov46Bracing
Dec41Bracing

UV index in Watertown in May

LowModerateHighVery highExtreme

Clear-sky midday UV in May peaks around 8 — 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 December 22 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 9Dec 22UV 1
UV index (midday)Level
Jan2Low
Feb3Moderate
Mar4Moderate
Apr6High
May8Very high
Jun9Very high
Jul8Very high
Aug8Very high
Sep6High
Oct3Moderate
Nov2Moderate
Dec1Low

Air quality in Watertown in May

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where May falls, not just the annual average.

Air quality in Watertown is worst in July — around 15 µg/m³ PM2.5 (moderate), about 2.0× the cleanest month (November, 8 µg/m³).

Modeled monthly averages (CAMS reanalysis, 2015–2024).

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateModerateGoodJul 1415 µg/m³Nov 118 µg/m³
PM2.5 (µg/m³)Level
Jan10Good
Feb12Moderate
Mar13Moderate
Apr12Good
May13Moderate
Jun14Moderate
Jul15Moderate
Aug14Moderate
Sep11Good
Oct8Good
Nov8Good
Dec9Good
Location & terrain

Where is Watertown?

Watertown sits at 43.2°N, 88.7°W, 853 ft above sea level, in United States. The nearest listed city is Oconomowoc, 13 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 180 ft around an average of 843 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 325 ft; within 50 miles, significant variations in elevation — a maximum elevation change of 1,129 ft.

The land around Watertown is covered by grassland (28%), artificial surfaces (27%) and trees (26%) within 2 miles, cropland (57%) and trees (21%) within 10 miles, and cropland (47%) and trees (26%) within 50 miles.

2 miles
180 ft
10 miles
325 ft
50 miles
1,129 ft
treesgrasslandcroplandartificial surfacesbare terrainwaterwetland
May weather nearby: Oconomowoc 13 mi · Beaver Dam 19 mi · Sun Prairie 24 mi · Waukesha 28 mi · Menomonee Falls 31 mi · Germantown 31 mi · West Bend 32 mi · Brookfield 33 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 (43.1947°, -88.729°, elevation 853 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. Sea temperatures are the NOAA OISST v2.1 1991–2020 monthly climatology (public domain), sampled at the nearest ocean point. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).