Mission Viejo weather in May

In May, Mission Viejo sees average daytime highs of 66°F and overnight lows near 58°F, with 0.3 in of rain across 1.7 wet days and about 13.7 hours of daylight. It is the 7th-warmest and 8th-wettest month of the year here.

Day-to-day highs hold fairly steady near 66°F through the month. The sky is clear or mostly clear about 57% 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 hours by month's end. Set against the rest of the year, May is Mission Viejo's 7th-clearest and 4th-windiest month. For the whole year in context, see Mission Viejo's year-round climate.

Daytime high
66°
7th warmest
Overnight low
58°
7th coldest
Rainfall
0.3 in
1.7 wet days
Daylight
13 h 42 min
4:55 AM – 6:39 PM
Cloud cover
37%
7th clearest
Wind
6 mph
4th windiest
Solar energy
7.16 kWh/m²
Travel score
7.7
out of 10

Mission Viejo is city in Orange County, California, United States.

Density
2,070/km²
people per km²
Founded
1988

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in May

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 66°F through the month.

A typical May day in Mission Viejo reaches about 66°F in the afternoon and slips back to 58°F overnight — a 8°F spread between the day's warmth and the night's chill. On most days the high lands between 61°F and 72°F. Set against its neighbours, May runs about 2°F warmer than April and about 3°F cooler than June.

50°60°70°80°151015202531
Avg high (°F)Avg low (°F)
16657
26657
36657
46657
56657
66657
76657
86657
96657
106658
116658
126658
136658
146658
156658
166658
176658
186658
196658
206658
216658
226658
236658
246658
256658
266658
276658
286659
296659
306759
316759

Mission Viejo weather by month

How May compares with the rest of the year at a glance. May is the 7th-warmest and 8th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysDaylight (hours)Travel score
Jan62° / 51°2.65.5106.2
Feb62° / 52°3.16.310.85.9
Mar63° / 53°1.85.711.76.3
Apr64° / 55°0.82.912.87.2
May66° / 58°0.31.713.77.7
Jun69° / 61°0.10.414.28.5
Jul73° / 64°0.10.4149.2
Aug75° / 66°0.00.213.29.6
Sep74° / 65°0.10.612.29.3
Oct71° / 61°0.6211.28.5
Nov67° / 56°0.82.810.37.7
Dec62° / 51°1.94.89.86.4

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 57% of the time in May.

Beyond those clear spells, partly cloudy skies cover about 18% of May, with mostly cloudy or overcast conditions the remaining 25%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
17327
27327
37228
47228
57228
67228
77228
87228
97228
107327
117426
127426
137426
147525
157525
167525
177525
187525
197624
207624
217624
227624
237723
247822
257822
267921
277921
287921
297921
308119
318119

Chance of precipitation in May

Any precipitation

Mission Viejo gets around 0.3 in of rain over 1.7 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 5% and peaks near 8% on the wettest days.

0%10%20%30%151015202531
Rain chance (%)
18
28
38
47
57
67
77
87
97
107
117
127
137
146
156
166
176
185
195
205
215
224
234
244
253
263
273
283
293
302
312

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 56% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)
167303
265323
364333
463343
562353
662353
761363
860373
960373
1059383
1159383
1259383
1357394
1457394
1557394
1657394
1756395
1856395
1956395
2056395
2155405
2253416
2353416
2452426
2551436
2650446
2748456
2847476
2946486
3044506
3142526

Wind in May

Winds average 6 mph in May.

Across May, daily wind ranges from about 5 mph on the calmest days to 6 mph at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (mph)Feels
16calm
26calm
36calm
46calm
56calm
66calm
76calm
86calm
96calm
106calm
116calm
126calm
136calm
146calm
156calm
166calm
176calm
186calm
196calm
206calm
216calm
226calm
236calm
246calm
256calm
265calm
275calm
285calm
295calm
305calm
315calm

Sunrise & sunset in May

DaylightNight

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

Days grow by about 42 minutes over May. Sunrise moves from 5:08 AM to 4:47 AM, and sunset from 6:27 PM to 6:49 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
113.35:086:27
213.35:076:28
313.45:066:29
413.45:056:30
513.45:046:31
613.55:036:31
713.55:026:32
813.55:016:33
913.65:016:34
1013.65:006:34
1113.64:596:35
1213.64:586:36
1313.74:576:37
1413.74:566:37
1513.74:566:38
1613.74:556:39
1713.84:546:40
1813.84:536:40
1913.84:536:41
2013.84:526:42
2113.94:526:43
2213.94:516:43
2313.94:506:44
2413.94:506:45
2513.94:496:45
2614.04:496:46
2714.04:486:47
2814.04:486:47
2914.04:476:48
3014.04:476:49
3114.04:476:49

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 7.16 kWh/m².

For context, solar energy here swings from a low near 3 kWh/m² to a high of 7.72 kWh/m² in June across the year — May's 7.16 kWh/m² falls in the middle.

02468151015202531
Solar energy (kWh/m²)Level
17.0Intense
27.0Intense
37.0Intense
47.0Intense
57.0Intense
67.0Intense
77.0Intense
87.1Intense
97.1Intense
107.1Intense
117.1Intense
127.1Intense
137.1Intense
147.1Intense
157.1Intense
167.1Intense
177.2Intense
187.2Intense
197.2Intense
207.2Intense
217.2Intense
227.2Intense
237.2Intense
247.3Intense
257.3Intense
267.3Intense
277.3Intense
287.3Intense
297.4Intense
307.4Intense
317.4Intense
Planning a trip in May

Is May a good time to visit Mission Viejo?

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

7.7
Sightseeing
6th-best month of the year
3.2
Beach & pool
7th-best month of the year

May is one of the better times to visit Mission Viejo for general sightseeing.

What to pack for Mission Viejo in May

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

In May, Mission Viejo sees daytime highs around 66°F and nights near 58°F. Pack sun protection.

sun protection

Sea temperature near Mission Viejo in May

The nearest coast averages about 63°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 12 mi away) is warmest in August at about 69°F and coldest in February near 59°F.

It's comfortable for a long swim from Jul 13 to Sep 28 — about 2.6 months when the water holds above 68°F.

60°65°70°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingcomfortable to swim
Sea temperature (°F)Comfort
Jan59Cool
Feb59Cool
Mar59Cool
Apr60Cool
May63Cool
Jun65Cool
Jul68Refreshing
Aug69Refreshing
Sep69Refreshing
Oct67Cool
Nov64Cool
Dec60Cool

UV index in Mission Viejo 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 Mission Viejo peaks around June 23 at about 10 (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.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateVery highExtremeVery highHighModerateJun 23UV 10Dec 16UV 3
UV index (midday)Level
Jan4Moderate
Feb5Moderate
Mar5Moderate
Apr8Very high
May8Very high
Jun11Extreme
Jul10Extreme
Aug10Extreme
Sep8Very high
Oct6High
Nov3Moderate
Dec3Moderate

Air quality in Mission Viejo 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 Mission Viejo is worst in September — around 49 µg/m³ PM2.5 (poor), about 4.0× the cleanest month (May, 12 µg/m³).

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

0204060JanFebMarAprMayJunJulAugSepOctNovDecModeratePoorModerateSep 1447 µg/m³May 1713 µg/m³
PM2.5 (µg/m³)Level
Jan18Moderate
Feb19Moderate
Mar19Moderate
Apr17Moderate
May12Moderate
Jun17Moderate
Jul19Moderate
Aug32Moderate
Sep49Poor
Oct21Moderate
Nov21Moderate
Dec18Moderate
Location & terrain

Where is Mission Viejo?

Mission Viejo sits at 33.6°N, 117.7°W, 397 ft above sea level, in United States. The nearest listed city is Laguna Hills, 2.5 mi away.

Topography around Mission Viejo

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

Within 2 miles, the terrain around Mission Viejo has only modest variations in elevation — a maximum elevation change of 561 ft around an average of 492 ft above sea level; within 10 miles, very significant variations in elevation — a maximum elevation change of 4,590 ft; within 50 miles, extreme variations in elevation — a maximum elevation change of 10,013 ft.

The land around Mission Viejo is covered by artificial surfaces (67%) and trees (25%) within 2 miles, trees (30%) and artificial surfaces (30%) within 10 miles, and water (31%) and artificial surfaces (26%) within 50 miles.

2 miles
561 ft
10 miles
4,590 ft
50 miles
10,013 ft
treesshrubsgrasslandcroplandartificial surfacesbare terrainwater
May weather nearby: Laguna Hills 2.5 mi · Ladera Ranch 3.1 mi · Laguna Woods 3.1 mi · Lake Forest 3.1 mi · Aliso Viejo 3.7 mi · Rancho Santa Margarita 5.0 mi · Laguna Niguel 5.6 mi · San Juan Capistrano 6.8 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 Mission Viejo (33.6°, -117.672°, elevation 397 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).