Ukiah weather in May

In May, Ukiah sees average daytime highs of 70°F and overnight lows near 47°F, with 1.9 in of rain across 5.4 wet days and about 14.1 hours of daylight. It is the 6th-warmest and 8th-wettest month of the year here.

Highs climb over the month, from about 68°F in the first days to 73°F by the end. The sky is clear or mostly clear about 53% of the time in May, and the air most often feels dry.

Daylight stretches from about 13 h 36 min at the start of May to 14 h 30 min by month's end. Set against the rest of the year, May is Ukiah's 6th-clearest and 2nd-windiest month. For the whole year in context, see Ukiah's year-round climate.

Daytime high
70°
6th warmest
Overnight low
47°
8th coldest
Rainfall
1.9 in
5.4 wet days
Daylight
14 h 06 min
5:05 AM – 7:13 PM
Cloud cover
42%
6th clearest
Wind
5 mph
2nd windiest
Solar energy
7.08 kWh/m²
Travel score
7.5
out of 10

Ukiah is city in and county seat of Mendocino County, California, United States.

Density
1,301/km²
people per km²
Founded
1876

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 68°F in the first days to 73°F by the end.

A typical May day in Ukiah reaches about 70°F in the afternoon and slips back to 47°F overnight — a 23°F spread between the day's warmth and the night's chill. On most days the high lands between 58°F and 83°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)
16745
26845
36845
46845
56846
66846
76946
86946
96946
106946
116946
126947
136947
146947
157047
167047
177047
187048
197148
207148
217148
227148
237149
247249
257249
267249
277349
287349
297350
307450
317450

How May really feels in Ukiah

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.

Ukiah weather by month

How May compares with the rest of the year at a glance. May is the 6th-warmest and 8th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan54° / 37°7.212.41.99.63.0
Feb56° / 38°6.710.82.310.53.6
Mar59° / 40°6.011.8211.74.5
Apr63° / 42°3.18.30.5135.9
May70° / 47°1.95.4014.17.5
Jun78° / 53°0.62.2014.78.6
Jul85° / 57°0.00.3014.57.1
Aug85° / 57°0.10.4013.57.2
Sep82° / 54°0.31.4012.38.3
Oct73° / 47°2.24.60118.1
Nov60° / 40°4.38.50.39.95.0
Dec53° / 36°7.812.21.39.32.9

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 53% 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 34%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
16040
26040
36139
46139
56139
66238
76238
86238
96238
106337
116337
126337
136337
146535
156535
166535
176634
186634
196634
206733
216832
226931
236931
247030
257030
267129
277129
287129
297129
307228
317228

Chance of precipitation in May

Any precipitation

Ukiah gets around 1.9 in of rain over 5.4 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 17% and peaks near 20% on the wettest days.

0%10%20%30%151015202531
Rain chance (%)
120
220
319
419
518
618
718
818
918
1018
1118
1218
1318
1418
1518
1618
1718
1818
1918
2018
2118
2217
2317
2416
2515
2615
2714
2814
2914
3013
3113

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 98% 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
11991
12991
13991
14991
15991
16991
17991
18982
19982
20982
21973
22973
23973
24964
25964
26955
27955
28955
29955
30946
31946

Wind in May

Winds average 5 mph in May.

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

0246810151015202531
Wind speed (mph)Feels
15calm
25calm
35calm
45calm
55calm
65calm
75calm
85calm
95calm
105calm
115calm
125calm
135calm
145calm
155calm
165calm
175calm
185calm
195calm
205calm
215calm
225calm
235calm
245calm
255calm
265calm
275calm
285calm
295calm
305calm
315calm

Sunrise & sunset in May

DaylightNight

Daylight runs from about 13 h 36 min at the start of May to 14 h 30 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 5:21 AM to 4:55 AM, and sunset from 6:59 PM to 7:26 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
113.65:216:59
213.75:207:00
313.75:197:01
413.75:187:02
513.85:177:03
613.85:157:04
713.85:147:05
813.95:137:06
913.95:127:07
1013.95:117:07
1114.05:107:08
1214.05:097:09
1314.05:087:10
1414.15:077:11
1514.15:067:12
1614.15:057:13
1714.25:047:14
1814.25:037:15
1914.25:027:16
2014.35:027:17
2114.35:017:18
2214.35:007:19
2314.34:597:19
2414.44:597:20
2514.44:587:21
2614.44:577:22
2714.44:577:23
2814.54:567:24
2914.54:567:24
3014.54:557:25
3114.54:557:26

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 7.08 kWh/m².

For context, solar energy here swings from a low near 1.92 kWh/m² to a high of 8.22 kWh/m² in July across the year — May's 7.08 kWh/m² falls in the middle.

02468151015202531
Solar energy (kWh/m²)Level
16.7Intense
26.7Intense
36.7Intense
46.8Intense
56.8Intense
66.8Intense
76.8Intense
86.9Intense
96.9Intense
106.9Intense
116.9Intense
127.0Intense
137.0Intense
147.0Intense
157.0Intense
167.0Intense
177.1Intense
187.1Intense
197.1Intense
207.2Intense
217.2Intense
227.2Intense
237.3Intense
247.3Intense
257.3Intense
267.4Intense
277.4Intense
287.4Intense
297.5Intense
307.5Intense
317.5Intense
Planning a trip in May

Hazard calendar for Ukiah

In seasonPeak

None of Ukiah's seasonal hazards are active in May. The full-year calendar below shows when the rainy season, cyclone risk and dust haze do peak.

Ukiah's rainy season runs November–March, 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 Ukiah?

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

7.5
Sightseeing
4th-best month of the year
4.8
Beach & pool
6th-best month of the year

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

What to pack for Ukiah in May

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

In May, Ukiah sees daytime highs around 70°F and nights near 47°F. Pack sun protection. About 5 days see rain.

sun protection

Sea temperature near Ukiah in May

The nearest coast averages about 52°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 29 mi away) is warmest in September at about 55°F and coldest in April near 52°F.

The water stays below 68°F all year — cool enough that most swimmers want a wetsuit.

50°52°54°56°JanFebMarAprMayJunJulAugSepOctNovDecbracing
Sea temperature (°F)Comfort
Jan53Bracing
Feb53Bracing
Mar53Bracing
Apr52Bracing
May52Bracing
Jun52Bracing
Jul53Bracing
Aug54Bracing
Sep55Bracing
Oct55Bracing
Nov55Bracing
Dec54Bracing

UV index in Ukiah in May

LowModerateHighVery highExtreme

Clear-sky midday UV in May peaks around 9 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Ukiah peaks around July 10 at about 10 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 15 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 highHighModerateLowJul 10UV 10Dec 15UV 2
UV index (midday)Level
Jan2Moderate
Feb3Moderate
Mar5Moderate
Apr6High
May9Very high
Jun10Very high
Jul10Extreme
Aug9Very high
Sep6High
Oct5Moderate
Nov2Moderate
Dec2Low

Air quality in Ukiah 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 Ukiah is worst in September — around 31 µg/m³ PM2.5 (moderate), about 5.8× the cleanest month (June, 5 µg/m³).

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

010203040JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodSep 1031 µg/m³Jun 106 µg/m³
PM2.5 (µg/m³)Level
Jan6Good
Feb8Good
Mar9Good
Apr8Good
May6Good
Jun5Good
Jul14Moderate
Aug29Moderate
Sep31Moderate
Oct14Moderate
Nov8Good
Dec6Good
Location & terrain

Where is Ukiah?

Ukiah sits at 39.2°N, 123.2°W, 633 ft above sea level, in United States. The nearest listed city is Clearlake, 34 mi away.

Topography around Ukiah

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

Within 2 miles, the terrain around Ukiah has significant variations in elevation — a maximum elevation change of 1,765 ft around an average of 827 ft above sea level; within 10 miles, large variations in elevation — a maximum elevation change of 3,415 ft; within 50 miles, very significant variations in elevation — a maximum elevation change of 7,362 ft.

The land around Ukiah is covered by trees (51%), artificial surfaces (25%) and grassland (20%) within 2 miles, trees (72%) and grassland (24%) within 10 miles, and trees (59%) and water (21%) within 50 miles.

2 miles
1,765 ft
10 miles
3,415 ft
50 miles
7,362 ft
treesgrasslandcroplandartificial surfacesbare terrainwater
May weather nearby: Clearlake 34 mi · Windsor 47 mi · Santa Rosa 56 mi · Rohnert Park 62 mi · Agua Caliente 69 mi · Petaluma 70 mi · Napa 77 mi · Novato 80 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 Ukiah (39.1502°, -123.2078°, elevation 633 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).