Highland weather in May

In May, Highland sees average daytime highs of 75°F and overnight lows near 52°F, with 0.3 in of rain across 2.5 wet days and about 13.8 hours of daylight. It is the 6th-warmest and 10th-wettest month of the year here.

Highs climb over the month, from about 72°F in the first days to 78°F by the end. The sky is clear or mostly clear about 69% of the time in May, and the air most often feels dry.

Daylight stretches from about 13 h 18 min at the start of May to 14 h 06 min by month's end. Set against the rest of the year, May is Highland's 6th-clearest and 3rd-windiest month. For the whole year in context, see Highland's year-round climate.

Daytime high
75°
6th warmest
Overnight low
52°
7th coldest
Rainfall
0.3 in
2.5 wet days
Daylight
13 h 48 min
4:52 AM – 6:38 PM
Cloud cover
28%
6th clearest
Wind
4 mph
3rd windiest
Solar energy
7.73 kWh/m²
Travel score
8.7
out of 10

Highland is city in San Bernardino County, California, United States.

Density
1,121/km²
people per km²
Founded
1891

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 72°F in the first days to 78°F by the end.

A typical May day in Highland reaches about 75°F in the afternoon and slips back to 52°F overnight — a 23°F spread between the day's warmth and the night's chill. On most days the high lands between 62°F and 86°F. Set against its neighbours, May runs about 7°F warmer than April and about 8°F cooler than June.

40°60°80°151015202531
Avg high (°F)Avg low (°F)
17249
27250
37250
47350
57350
67350
77351
87351
97351
107451
117451
127451
137451
147451
157452
167452
177452
187552
197552
207552
217552
227553
237653
247653
257653
267653
277753
287754
297854
307854
317855

How May really feels in Highland

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.

Highland weather by month

How May compares with the rest of the year at a glance. May is the 6th-warmest and 10th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan57° / 40°2.25.60.9104.7
Feb58° / 40°2.76.61.110.74.8
Mar62° / 43°1.65.70.911.76.2
Apr68° / 46°0.83.30.312.87.7
May75° / 52°0.32.5013.88.7
Jun83° / 58°0.10.7014.27.8
Jul89° / 65°0.52.90145.4
Aug89° / 65°0.43013.35.3
Sep85° / 61°0.31.6012.27.2
Oct75° / 53°0.52.1011.18.8
Nov64° / 45°0.72.90.210.27.2
Dec57° / 39°1.74.60.59.84.7

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 69% of the time in May.

Beyond those clear spells, partly cloudy skies cover about 13% of May, with mostly cloudy or overcast conditions the remaining 18%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
17822
27822
37822
47822
57921
67921
77921
87822
97822
107822
117921
127921
137921
148119
158119
168119
178218
188218
198218
208416
218416
228416
238515
248515
258515
268614
278614
288614
298713
308713
318713

Chance of precipitation in May

Any precipitation

Highland gets around 0.3 in of rain over 2.5 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 8% and peaks near 9% on the wettest days.

0%10%20%30%151015202531
Rain chance (%)
19
29
39
49
59
69
79
89
99
109
119
129
139
149
159
169
179
189
199
209
218
228
238
248
257
267
277
286
296
305
315

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
241000
251000
261000
271000
28991
29991
30991
31991

Wind in May

Winds average 4 mph in May.

Across May, daily wind ranges from about 4 mph on the calmest days to 4 mph at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (mph)Feels
14calm
24calm
34calm
44calm
54calm
64calm
74calm
84calm
94calm
104calm
114calm
124calm
134calm
144calm
154calm
164calm
174calm
184calm
194calm
204calm
214calm
224calm
234calm
244calm
254calm
264calm
274calm
284calm
294calm
304calm
314calm

Sunrise & sunset in May

DaylightNight

Daylight runs from about 13 h 18 min at the start of May to 14 h 06 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 48 minutes over May. Sunrise moves from 5:06 AM to 4:44 AM, and sunset from 6:26 PM to 6:49 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
113.35:066:26
213.45:056:27
313.45:046:28
413.45:036:29
513.55:026:30
613.55:016:30
713.55:006:31
813.64:596:32
913.64:586:33
1013.64:576:34
1113.64:566:34
1213.74:556:35
1313.74:546:36
1413.74:536:37
1513.74:536:37
1613.84:526:38
1713.84:516:39
1813.84:516:40
1913.84:506:40
2013.94:496:41
2113.94:496:42
2213.94:486:43
2313.94:476:43
2414.04:476:44
2514.04:466:45
2614.04:466:46
2714.04:456:46
2814.04:456:47
2914.14:446:48
3014.14:446:48
3114.14:446:49

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 7.73 kWh/m².

For context, solar energy here swings from a low near 3.04 kWh/m² to a high of 8.39 kWh/m² in June across the year — May's 7.73 kWh/m² sits near the top of that range.

02468151015202531
Solar energy (kWh/m²)Level
17.4Intense
27.5Intense
37.5Intense
47.5Intense
57.5Intense
67.5Intense
77.5Intense
87.6Intense
97.6Intense
107.6Intense
117.6Intense
127.6Intense
137.7Intense
147.7Intense
157.7Intense
167.7Intense
177.7Intense
187.8Intense
197.8Intense
207.8Intense
217.8Intense
227.8Intense
237.9Intense
247.9Intense
257.9Intense
268.0Intense
278.0Intense
288.0Intense
298.0Intense
308.1Intense
318.1Intense
Planning a trip in May

Is May a good time to visit Highland?

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

8.7
Sightseeing
2nd-best month of the year
7.1
Beach & pool
6th-best month of the year

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

What to pack for Highland in May

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

In May, Highland sees daytime highs around 75°F and nights near 52°F. Pack sun protection. Worth having: light clothes.

sun protectionlight clothes

UV index in Highland in May

LowModerateHighVery highExtreme

Clear-sky midday UV in May peaks around 8 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Highland peaks around June 23 at about 11 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 16 at about 3 (moderate).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 11 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highExtremeVery highHighModerateJun 23UV 11Dec 16UV 3
UV index (midday)Level
Jan4Moderate
Feb5Moderate
Mar5High
Apr8Very high
May8Very high
Jun11Extreme
Jul11Extreme
Aug11Extreme
Sep8Very high
Oct6High
Nov4Moderate
Dec3Moderate

Air quality in Highland 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 Highland is worst in September — around 30 µg/m³ PM2.5 (moderate), about 5.3× the cleanest month (December, 6 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodSep 1427 µg/m³Dec 146 µg/m³
PM2.5 (µg/m³)Level
Jan6Good
Feb7Good
Mar9Good
Apr9Good
May9Good
Jun16Moderate
Jul12Good
Aug15Moderate
Sep30Moderate
Oct7Good
Nov6Good
Dec6Good
Location & terrain

Where is Highland?

Highland sits at 34.1°N, 117.2°W, 1,309 ft above sea level, in United States. The nearest listed city is San Bernardino, 5.0 mi away.

Topography around Highland

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

Within 2 miles, the terrain around Highland has significant variations in elevation — a maximum elevation change of 1,558 ft around an average of 1,394 ft above sea level; within 10 miles, very significant variations in elevation — a maximum elevation change of 6,699 ft; within 50 miles, extreme variations in elevation — a maximum elevation change of 11,411 ft.

The land around Highland is covered by artificial surfaces (57%) within 2 miles, trees (28%), artificial surfaces (28%) and shrubs (24%) within 10 miles, and shrubs (29%) and bare terrain (21%) within 50 miles.

2 miles
1,558 ft
10 miles
6,699 ft
50 miles
11,411 ft
treesshrubsgrasslandcroplandartificial surfacesbare terrainwater
May weather nearby: San Bernardino 5.0 mi · Redlands 5.0 mi · Loma Linda 6.2 mi · Colton 6.8 mi · Rialto 9.3 mi · Bloomington 11 mi · Yucaipa 12 mi · Fontana 13 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 Highland (34.1283°, -117.2087°, elevation 1,309 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).