Grand Forks weather in May

In May, Grand Forks sees average daytime highs of 66°F and overnight lows near 45°F, with 3.4 in of precipitation across 11.2 wet days and about 14.9 hours of daylight. It is the 5th-warmest and 3rd-wettest month of the year here.

Highs climb over the month, from about 61°F in the first days to 71°F by the end. The sky is clear or mostly clear about 26% of the time in May, and the air most often feels dry.

Daylight stretches from about 14 h 12 min at the start of May to 15 h 30 min by month's end. Set against the rest of the year, May is Grand Forks's 5th-clearest and 2nd-windiest month. For the whole year in context, see Grand Forks's year-round climate.

Daytime high
66°
5th warmest
Overnight low
45°
8th coldest
Precipitation
3.4 in
11.2 wet days
Daylight
14 h 54 min
4:56 AM – 7:53 PM
Cloud cover
63%
5th clearest
Wind
9 mph
2nd windiest
Solar energy
5.71 kWh/m²
Travel score
5.7
out of 10

Grand Forks is city in North Dakota, United States.

Density
810/km²
people per km²
Founded
1870

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 71°F by the end.

A typical May day in Grand Forks reaches about 66°F in the afternoon and slips back to 45°F overnight — a 21°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 14°F warmer than April and about 9°F cooler than June.

20°40°60°80°151015202531
Avg high (°F)Avg low (°F)
16038
26039
36139
46140
56140
66240
76241
86241
96342
106342
116442
126443
136543
146544
156544
166645
176645
186746
196746
206847
216847
226847
236948
246948
257049
267049
277050
287150
297151
307151
317251

How May really feels in Grand Forks

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.

Grand Forks weather by month

How May compares with the rest of the year at a glance. May is the 5th-warmest and 3rd-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan16° / -1°0.75.15.38.60.0
Feb21° / 0.63.94.29.90.0
Mar35° / 17°1.264.211.60.1
Apr52° / 32°1.77.42.113.42.9
May66° / 45°3.411.20.214.95.7
Jun75° / 56°4.112.2015.76.5
Jul79° / 59°3.510.1015.46.8
Aug78° / 56°3.19.2014.17.1
Sep68° / 47°2.78012.46.6
Oct53° / 35°2.37.91.310.63.1
Nov35° / 20°1.15.44.190.0
Dec21° / 1.05.96.48.30.0

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 26% of the time in May.

Beyond those clear spells, partly cloudy skies cover about 16% of May, with mostly cloudy or overcast conditions the remaining 59%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14357
24357
34258
44258
54258
64258
74258
84258
94258
104258
114159
124258
134159
144159
154258
164159
174159
184159
194159
204159
214159
224159
234159
244159
254060
264159
274060
284159
294159
304159
314258

Chance of precipitation in May

Any precipitationSnow

Grand Forks gets around 3.4 in of rain and snow over 11.2 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 36% and peaks near 38% on the wettest days, and about 0 day brings snow.

0%10%20%30%40%50%151015202531
Rain chance (%)Snow chance (%)
1323
2343
3353
4363
5362
6372
7372
8382
9382
10381
11381
12371
13371
14371
15361
16361
17350
18350
19350
20340
21340
22340
23340
24340
25350
26350
27350
28350
29350
30350
31360

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 92% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)
19910
29910
39820
49820
59820
69820
79820
89730
99730
109631
119541
129541
139451
149451
159361
169361
179172
189172
199082
209082
218992
2288102
2387103
2486113
2586113
2685123
2784133
2884133
2983143
3082144
3181154

Wind in May

Winds average 9 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
79light breeze
89light breeze
99light breeze
109light breeze
119light breeze
129light breeze
139light breeze
149light breeze
159light breeze
169light breeze
179light breeze
189light breeze
199light breeze
209light breeze
219light breeze
229light breeze
239light 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 14 h 12 min at the start of May to 15 h 30 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 78 minutes over May. Sunrise moves from 5:19 AM to 4:41 AM, and sunset from 7:32 PM to 8:10 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
114.25:197:32
214.35:177:33
314.35:157:35
414.45:147:36
514.45:127:38
614.55:117:39
714.55:097:40
814.65:077:42
914.65:067:43
1014.75:047:45
1114.75:037:46
1214.85:027:47
1314.85:007:49
1414.94:597:50
1514.94:577:51
1614.94:567:53
1715.04:557:54
1815.04:547:55
1915.14:527:56
2015.14:517:58
2115.14:507:59
2215.24:498:00
2315.24:488:01
2415.34:478:03
2515.34:468:04
2615.34:458:05
2715.44:448:06
2815.44:438:07
2915.44:428:08
3015.54:428:09
3115.54:418:10

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 5.71 kWh/m².

For context, solar energy here swings from a low near 1.21 kWh/m² to a high of 6.23 kWh/m² in July across the year — May's 5.71 kWh/m² sits near the top of that range.

0246151015202531
Solar energy (kWh/m²)Level
15.5Bright
25.5Bright
35.5Bright
45.5Bright
55.5Bright
65.5Bright
75.5Bright
85.5Bright
95.6Bright
105.6Bright
115.6Bright
125.6Bright
135.6Bright
145.7Bright
155.7Bright
165.7Bright
175.7Bright
185.8Bright
195.8Bright
205.8Bright
215.8Bright
225.8Bright
235.8Bright
245.9Bright
255.9Bright
265.9Bright
275.9Bright
285.9Bright
295.9Bright
305.9Bright
316.0Bright
Planning a trip in May

Hazard calendar for Grand Forks

In seasonPeak

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

Grand Forks's rainy season runs May–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 Grand Forks?

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
2.4
Beach & pool
5th-best month of the year

May is a reasonable time to visit Grand Forks for sightseeing.

What to pack for Grand Forks in May

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

In May, Grand Forks sees daytime highs around 66°F and nights near 45°F. Worth packing: a warm layer, rain gear and sun protection. About 11 days see rain.

a warm layerrain gearsun protection

UV index in Grand Forks in May

LowModerateHighVery highExtreme

Clear-sky midday UV in May peaks around 5 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Grand Forks peaks around June 19 at about 8 (very high) — sunscreen and a hat are worth it in the middle of the day. 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 7 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighVery highHighModerateLowJun 19UV 8Jan 1UV 1
UV index (midday)Level
Jan1Low
Feb1Low
Mar3Moderate
Apr4Moderate
May5High
Jun8Very high
Jul7High
Aug7High
Sep5Moderate
Oct3Moderate
Nov1Low
Dec1Low

Air quality in Grand Forks 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 Grand Forks is worst in August — around 16 µg/m³ PM2.5 (moderate), about 2.8× the cleanest month (October, 6 µg/m³).

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

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodModerateGoodAug 916 µg/m³Oct 216 µg/m³
PM2.5 (µg/m³)Level
Jan9Good
Feb10Good
Mar14Moderate
Apr12Good
May11Good
Jun11Good
Jul16Moderate
Aug16Moderate
Sep10Good
Oct6Good
Nov7Good
Dec8Good
Location & terrain

Where is Grand Forks?

Grand Forks sits at 47.9°N, 97.0°W, 830 ft above sea level, in United States. The nearest listed city is West Fargo, 73 mi away.

Topography around Grand Forks

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

Within 2 miles, the terrain around Grand Forks has only modest variations in elevation — a maximum elevation change of 98 ft around an average of 833 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 141 ft; within 50 miles, only modest variations in elevation — a maximum elevation change of 807 ft.

The land around Grand Forks is covered by artificial surfaces (35%), trees (26%) and grassland (25%) within 2 miles, cropland (74%) within 10 miles, and cropland (81%) within 50 miles.

2 miles
98 ft
10 miles
141 ft
50 miles
807 ft
treesgrasslandcroplandartificial surfacesbare terrainwater
May weather nearby: West Fargo 73 mi · Fargo 73 mi · Moorhead 74 mi · Jamestown 105 mi · Steinbach 112 mi · Fort Garry South 129 mi · Winnipeg 135 mi · St. James-Assiniboia East 136 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 Grand Forks (47.9253°, -97.0328°, elevation 830 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. 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).