Greeley weather in May

In May, Greeley sees average daytime highs of 71°F and overnight lows near 45°F, with 2.6 in of precipitation across 9.8 wet days and about 14.2 hours of daylight. It is the 5th-warmest and 1st-wettest month of the year here.

Highs climb over the month, from about 66°F in the first days to 75°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 13 h 42 min at the start of May to 14 h 36 min by month's end. Set against the rest of the year, May is Greeley's 12th-clearest and 2nd-windiest month. For the whole year in context, see Greeley's year-round climate.

Daytime high
71°
5th warmest
Overnight low
45°
8th coldest
Precipitation
2.6 in
9.8 wet days
Daylight
14 h 12 min
4:48 AM – 7:02 PM
Cloud cover
60%
12th clearest
Wind
6 mph
2nd windiest
Solar energy
6.63 kWh/m²
Travel score
6.6
out of 10

Greeley is city in and county seat of Weld County, Colorado, United States.

Density
876/km²
people per km²
Founded
1869

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 66°F in the first days to 75°F by the end.

A typical May day in Greeley reaches about 71°F in the afternoon and slips back to 45°F overnight — a 26°F spread between the day's warmth and the night's chill. On most days the high lands between 56°F and 84°F. Set against its neighbours, May runs about 9°F warmer than April and about 11°F cooler than June.

40°60°80°151015202531
Avg high (°F)Avg low (°F)
16540
26640
36641
46741
56742
66742
76842
86843
96943
106943
116944
127044
137044
147145
157145
167146
177146
187246
197246
207247
217347
227347
237348
247348
257448
267449
277449
287549
297550
307650
317650

How May really feels in Greeley

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.

Greeley weather by month

How May compares with the rest of the year at a glance. May is the 5th-warmest and 1st-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan41° / 19°0.42.93.39.40.2
Feb45° / 21°0.43.43.410.41.2
Mar55° / 29°1.15.43.211.74.0
Apr62° / 36°1.98.52.7135.5
May71° / 45°2.69.80.614.26.6
Jun82° / 55°1.67.3014.86.4
Jul88° / 61°1.47.5014.64.7
Aug86° / 59°1.26.6013.65.5
Sep78° / 50°1.14.60.312.37.7
Oct64° / 38°1.25.11.410.96.5
Nov51° / 27°0.63.82.99.82.9
Dec41° / 20°0.42.939.20.2

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 26% of the time in May, the cloudiest month of the year.

Beyond those clear spells, partly cloudy skies cover about 24% of May, with mostly cloudy or overcast conditions the remaining 50%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14951
24951
35050
45050
55149
65149
75050
85050
95050
105149
115050
125050
134951
144951
154951
164951
174951
184852
194852
204852
214852
224852
234852
244951
254852
264852
275050
285050
295248
305347
315446

Chance of precipitation in May

Any precipitationSnow

Greeley gets around 2.6 in of rain and snow over 9.8 wet days in May, the wettest month. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable precipitation averages around 31% and peaks near 33% on the wettest days, and about 1 day brings snow.

0%10%20%30%40%151015202531
Rain chance (%)Snow chance (%)
1325
2325
3325
4314
5314
6314
7304
8303
9293
10293
11293
12293
13293
14303
15302
16312
17312
18312
19322
20322
21331
22331
23331
24331
25331
26331
27331
28330
29330
30320
31320

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 100% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)
11000
21000
31000
41000
51000
61000
71000
81000
91000
101000
111000
121000
131000
141000
151000
161000
171000
181000
191000
201000
211000
221000
231000
24991
25991
26991
27991
28991
29982
30982
31982

Wind in May

Winds average 6 mph in May.

Across May, daily wind ranges from about 6 mph on the calmest days to 7 mph at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (mph)Feels
17calm
27calm
37calm
47calm
57calm
67calm
77calm
87calm
97calm
107calm
117calm
127calm
137calm
146calm
156calm
166calm
176calm
186calm
196calm
206calm
216calm
226calm
236calm
246calm
256calm
266calm
276calm
286calm
296calm
306calm
316calm

Sunrise & sunset in May

DaylightNight

Daylight runs from about 13 h 42 min at the start of May to 14 h 36 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 54 minutes over May. Sunrise moves from 5:05 AM to 4:37 AM, and sunset from 6:47 PM to 7:15 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
113.75:056:47
213.75:046:48
313.85:036:49
413.85:016:50
513.95:006:51
613.94:596:52
713.94:586:53
814.04:566:54
914.04:556:55
1014.04:546:56
1114.14:536:57
1214.14:526:58
1314.14:516:59
1414.24:507:00
1514.24:497:01
1614.24:487:02
1714.34:477:03
1814.34:467:04
1914.34:457:05
2014.44:447:06
2114.44:447:07
2214.44:437:08
2314.44:427:09
2414.54:417:10
2514.54:417:11
2614.54:407:11
2714.64:397:12
2814.64:397:13
2914.64:387:14
3014.64:377:15
3114.64:377:15

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 6.63 kWh/m².

For context, solar energy here swings from a low near 2.34 kWh/m² to a high of 7.29 kWh/m² in June across the year — May's 6.63 kWh/m² sits near the top of that range.

0246151015202531
Solar energy (kWh/m²)Level
16.4Intense
26.4Intense
36.4Intense
46.5Intense
56.5Intense
66.5Intense
76.5Intense
86.5Intense
96.6Intense
106.6Intense
116.6Intense
126.6Intense
136.6Intense
146.6Intense
156.6Intense
166.6Intense
176.7Intense
186.7Intense
196.7Intense
206.7Intense
216.7Intense
226.7Intense
236.7Intense
246.7Intense
256.7Intense
266.8Intense
276.8Intense
286.8Intense
296.8Intense
306.9Intense
316.9Intense
Planning a trip in May

Is May a good time to visit Greeley?

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

6.6
Sightseeing
2nd-best month of the year
4.4
Beach & pool
5th-best month of the year

May is a reasonable time to visit Greeley for sightseeing.

What to pack for Greeley in May

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

In May, Greeley sees daytime highs around 71°F and nights near 45°F. Pack sun protection. Worth having: a warm layer and rain gear. About 10 days see rain.

sun protectiona warm layerrain gear

UV index in Greeley in May

LowModerateHighVery highExtreme

Clear-sky midday UV in May peaks around 7 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Greeley peaks around July 13 at about 11 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 23 at about 2 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 9 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highExtremeVery highHighModerateJul 13UV 11Dec 23UV 2
UV index (midday)Level
Jan2Low
Feb3Moderate
Mar6High
Apr6High
May7Very high
Jun10Extreme
Jul11Extreme
Aug9Very high
Sep7High
Oct5Moderate
Nov3Moderate
Dec2Low

Air quality in Greeley 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 Greeley is worst in October — around 30 µg/m³ PM2.5 (moderate), about 3.1× the cleanest month (November, 10 µg/m³).

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

010203040JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodModerateGoodOct 1528 µg/m³Nov 2310 µg/m³
PM2.5 (µg/m³)Level
Jan12Good
Feb12Moderate
Mar14Moderate
Apr11Good
May11Good
Jun12Good
Jul14Moderate
Aug19Moderate
Sep17Moderate
Oct30Moderate
Nov10Good
Dec11Good
Location & terrain

Where is Greeley?

Greeley sits at 40.4°N, 104.7°W, 4,675 ft above sea level, in United States. The nearest listed city is Evans, 3.1 mi away.

Topography around Greeley

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

Within 2 miles, the terrain around Greeley has only modest variations in elevation — a maximum elevation change of 226 ft around an average of 4,705 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 505 ft; within 50 miles, extreme variations in elevation — a maximum elevation change of 9,862 ft.

The land around Greeley is covered by artificial surfaces (51%) within 2 miles, cropland (55%) and grassland (29%) within 10 miles, and grassland (61%) and cropland (21%) within 50 miles.

2 miles
226 ft
10 miles
505 ft
50 miles
9,862 ft
treesgrasslandcroplandartificial surfacesbare terrainwater
May weather nearby: Evans 3.1 mi · Windsor 11 mi · Loveland 19 mi · Fort Collins 22 mi · Longmont 27 mi · Brighton 31 mi · Erie 32 mi · Lafayette 36 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 Greeley (40.4233°, -104.7091°, elevation 4,675 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).