Tōmi weather in May

In May, Tōmi sees average daytime highs of 20°C and overnight lows near 9°C, with 108 mm of rain across 11.1 wet days and about 13.9 hours of daylight. It is the 5th-warmest and 5th-wettest month of the year here.

Highs climb over the month, from about 18°C in the first days to 21°C by the end. The sky is clear or mostly clear about 28% of the time in May, and the air most often feels dry.

Daylight stretches from about 13 h 30 min at the start of May to 14 h 18 min by month's end. Set against the rest of the year, May is Tōmi's 8th-clearest and 5th-windiest month. For the whole year in context, see Tōmi's year-round climate.

Daytime high: 20°; 5th warmest
Overnight low: 9°; 8th coldest
Rainfall: 108 mm; 11.1 wet days
Daylight: 13 h 54 min; 4:45 AM – 6:41 PM
Cloud cover: 64%; 8th clearest
Wind: 6 km/h; 5th windiest
Solar energy: 5.79 kWh/m²
Travel score: 6.1; out of 10

Tōmi is city in Nagano Prefecture, Japan.

Density: 268/km²; people per km²
Founded: 2004

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

← April Tōmi year-round climate June →Best places to visit in May

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Temperature in May

Average highAverage lowShaded bands: 10–90% of days

Highs climb over the month, from about 18°C in the first days to 21°C by the end.

A typical May day in Tōmi reaches about 20°C in the afternoon and slips back to 9°C overnight — a 11°C spread between the day's warmth and the night's chill. On most days the high lands between 15°C and 24°C. Set against its neighbours, May runs about 5°C warmer than April and about 3°C cooler than June.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30	31
Avg high (°C)	18	18	18	18	18	19	19	19	19	19	19	19	19	20	20	20	20	20	20	20	20	21	21	21	21	21	21	21	21	21	22
Avg low (°C)	7	7	7	7	8	8	8	8	8	8	9	9	9	9	9	9	9	10	10	10	10	10	10	11	11	11	11	11	11	12	12

	Avg high (°C)	Avg low (°C)
1	18	7
2	18	7
3	18	7
4	18	7
5	18	8
6	19	8
7	19	8
8	19	8
9	19	8
10	19	8
11	19	9
12	19	9
13	19	9
14	20	9
15	20	9
16	20	9
17	20	9
18	20	10
19	20	10
20	20	10
21	20	10
22	21	10
23	21	10
24	21	11
25	21	11
26	21	11
27	21	11
28	21	11
29	21	11
30	21	12
31	22	12

How May really feels in Tōmi

Once humidity and wind are folded in, May averages 0 days that feel above 32°C and 0 that feel at or below 0°C — the comfort signal a plain temperature reading hides.

Days feeling ≥ 32°C

heat index over the day's high

Days feeling ≤ 0°C

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.

Tōmi weather by month

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

Month	High / Low (°C)	Rainfall (mm)	Wet days	Snow days	Daylight (hours)	Travel score
Jan	3° / -6°	62	9.8	10.1	9.8	0.0
Feb	4° / -5°	65	9.4	8.2	10.6	0.0
Mar	8° / -2°	107	12.4	7.3	11.7	1.3
Apr	14° / 4°	100	11.4	1.8	12.9	4.2
May	20° / 9°	108	11.1	0	13.9	6.1
Jun	23° / 14°	141	13.7	0	14.4	5.8
Jul	26° / 18°	161	14.5	0	14.2	5.7
Aug	28° / 19°	98	11.5	0	13.4	5.9
Sep	24° / 15°	137	11.7	0	12.2	6.3
Oct	17° / 9°	143	10.8	0	11.1	5.5
Nov	12° / 2°	70	9	1.1	10.1	3.1
Dec	6° / -2°	59	9.6	7	9.6	0.5

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 28% of the time in May.

Beyond those clear spells, partly cloudy skies cover about 14% of May, with mostly cloudy or overcast conditions the remaining 58%. Skies tend to cloud over as the month goes on.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30	31
Clearer (%)	48	47	46	47	46	46	45	44	44	43	42	43	42	42	42	42	42	41	41	41	41	40	40	40	39	38	38	37	37	35	34
Cloudier (%)	52	53	54	53	54	54	55	56	56	57	58	57	58	58	58	58	58	59	59	59	59	60	60	60	61	62	62	63	63	65	66

	Clearer (%)	Cloudier (%)
1	48	52
2	47	53
3	46	54
4	47	53
5	46	54
6	46	54
7	45	55
8	44	56
9	44	56
10	43	57
11	42	58
12	43	57
13	42	58
14	42	58
15	42	58
16	42	58
17	42	58
18	41	59
19	41	59
20	41	59
21	41	59
22	40	60
23	40	60
24	40	60
25	39	61
26	38	62
27	38	62
28	37	63
29	37	63
30	35	65
31	34	66

Chance of precipitation in May

Any precipitation

Tōmi gets around 108 mm of rain over 11.1 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 35% and peaks near 37% on the wettest days.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30	31
Rain chance (%)	33	32	32	33	33	33	34	34	35	35	35	36	36	36	37	37	37	37	36	36	36	36	36	36	35	35	35	34	34	34	35

	Rain chance (%)
1	33
2	32
3	32
4	33
5	33
6	33
7	34
8	34
9	35
10	35
11	35
12	36
13	36
14	36
15	37
16	37
17	37
18	37
19	36
20	36
21	36
22	36
23	36
24	36
25	35
26	35
27	35
28	34
29	34
30	34
31	35

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 96% of days. It rarely turns muggy — the humid and sticky bands barely register.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30	31
Dry (%)	99	98	98	98	98	98	98	97	97	97	97	97	96	96	96	96	96	96	96	96	96	95	95	95	95	95	95	94	94	93	92
Comfortable (%)	1	2	2	2	2	2	2	3	3	3	3	3	4	4	4	4	4	4	4	4	4	5	5	5	5	5	5	6	6	7	8

	Dry (%)	Comfortable (%)
1	99	1
2	98	2
3	98	2
4	98	2
5	98	2
6	98	2
7	98	2
8	97	3
9	97	3
10	97	3
11	97	3
12	97	3
13	96	4
14	96	4
15	96	4
16	96	4
17	96	4
18	96	4
19	96	4
20	96	4
21	96	4
22	95	5
23	95	5
24	95	5
25	95	5
26	95	5
27	95	5
28	94	6
29	94	6
30	93	7
31	92	8

Wind in May

Winds average 6 km/h in May.

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

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30	31
Wind speed (km/h)	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	5	5	5	5	5	5
Feels	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm

	Wind speed (km/h)	Feels
1	6	calm
2	6	calm
3	6	calm
4	6	calm
5	6	calm
6	6	calm
7	6	calm
8	6	calm
9	6	calm
10	6	calm
11	6	calm
12	6	calm
13	6	calm
14	6	calm
15	6	calm
16	6	calm
17	6	calm
18	6	calm
19	6	calm
20	6	calm
21	6	calm
22	6	calm
23	6	calm
24	6	calm
25	6	calm
26	5	calm
27	5	calm
28	5	calm
29	5	calm
30	5	calm
31	5	calm

Sunrise & sunset in May

DaylightNight

Daylight runs from about 13 h 30 min at the start of May to 14 h 18 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 5:00 AM to 4:36 AM, and sunset from 6:28 PM to 6:52 PM.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30	31
Daylight (h)	13.5	13.5	13.5	13.6	13.6	13.6	13.7	13.7	13.7	13.8	13.8	13.8	13.8	13.9	13.9	13.9	14.0	14.0	14.0	14.0	14.1	14.1	14.1	14.1	14.2	14.2	14.2	14.2	14.2	14.3	14.3
Sunrise (AM)	5:00	4:59	4:58	4:56	4:55	4:54	4:53	4:52	4:51	4:50	4:49	4:48	4:48	4:47	4:46	4:45	4:44	4:43	4:43	4:42	4:41	4:41	4:40	4:39	4:39	4:38	4:38	4:37	4:37	4:36	4:36
Sunset (PM)	6:28	6:29	6:29	6:30	6:31	6:32	6:33	6:34	6:35	6:36	6:36	6:37	6:38	6:39	6:40	6:41	6:41	6:42	6:43	6:44	6:45	6:45	6:46	6:47	6:48	6:49	6:49	6:50	6:51	6:51	6:52

	Daylight (h)	Sunrise (AM)	Sunset (PM)
1	13.5	5:00	6:28
2	13.5	4:59	6:29
3	13.5	4:58	6:29
4	13.6	4:56	6:30
5	13.6	4:55	6:31
6	13.6	4:54	6:32
7	13.7	4:53	6:33
8	13.7	4:52	6:34
9	13.7	4:51	6:35
10	13.8	4:50	6:36
11	13.8	4:49	6:36
12	13.8	4:48	6:37
13	13.8	4:48	6:38
14	13.9	4:47	6:39
15	13.9	4:46	6:40
16	13.9	4:45	6:41
17	14.0	4:44	6:41
18	14.0	4:43	6:42
19	14.0	4:43	6:43
20	14.0	4:42	6:44
21	14.1	4:41	6:45
22	14.1	4:41	6:45
23	14.1	4:40	6:46
24	14.1	4:39	6:47
25	14.2	4:39	6:48
26	14.2	4:38	6:49
27	14.2	4:38	6:49
28	14.2	4:37	6:50
29	14.2	4:37	6:51
30	14.3	4:36	6:51
31	14.3	4:36	6:52

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 5.79 kWh/m² — the sunniest month for solar.

For context, solar energy here swings from a low near 2.51 kWh/m² to a high of 5.79 kWh/m² in May across the year — May's 5.79 kWh/m² sits near the top of that range.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30	31
Solar energy (kWh/m²)	5.7	5.7	5.7	5.7	5.8	5.8	5.8	5.8	5.8	5.8	5.8	5.8	5.8	5.8	5.8	5.8	5.8	5.8	5.8	5.8	5.8	5.9	5.9	5.8	5.8	5.8	5.8	5.8	5.8	5.8	5.8
Level	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright

	Solar energy (kWh/m²)	Level
1	5.7	Bright
2	5.7	Bright
3	5.7	Bright
4	5.7	Bright
5	5.8	Bright
6	5.8	Bright
7	5.8	Bright
8	5.8	Bright
9	5.8	Bright
10	5.8	Bright
11	5.8	Bright
12	5.8	Bright
13	5.8	Bright
14	5.8	Bright
15	5.8	Bright
16	5.8	Bright
17	5.8	Bright
18	5.8	Bright
19	5.8	Bright
20	5.8	Bright
21	5.8	Bright
22	5.9	Bright
23	5.9	Bright
24	5.8	Bright
25	5.8	Bright
26	5.8	Bright
27	5.8	Bright
28	5.8	Bright
29	5.8	Bright
30	5.8	Bright
31	5.8	Bright

Planning a trip in May

Is May a good time to visit Tōmi?

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

6.1

Sightseeing

2nd-best month of the year

3.0

Beach & pool

5th-best month of the year

May is a reasonable time to visit Tōmi for sightseeing.

What to pack for Tōmi in May

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

In May, Tōmi sees daytime highs around 20°C and nights near 9°C. Worth packing: rain gear and sun protection. About 11 days see rain.

rain gearsun protection

UV index in Tōmi 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 Tōmi peaks around July 18 at about 10 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 22 at about 2 (moderate).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 10 months of the year.

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
UV index (midday)	3	4	5	7	9	10	10	10	9	6	3	2
Level	Moderate	Moderate	High	Very high	Very high	Very high	Very high	Very high	Very high	High	Moderate	Moderate

	UV index (midday)	Level
Jan	3	Moderate
Feb	4	Moderate
Mar	5	High
Apr	7	Very high
May	9	Very high
Jun	10	Very high
Jul	10	Very high
Aug	10	Very high
Sep	9	Very high
Oct	6	High
Nov	3	Moderate
Dec	2	Moderate

Air quality in Tōmi 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 Tōmi is worst in April — around 18 µg/m³ PM2.5 (moderate), about 2.3× the cleanest month (December, 8 µg/m³).

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

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
PM2.5 (µg/m³)	9	11	17	18	17	16	13	12	10	10	9	8
Level	Good	Good	Moderate	Moderate	Moderate	Moderate	Moderate	Good	Good	Good	Good	Good

	PM2.5 (µg/m³)	Level
Jan	9	Good
Feb	11	Good
Mar	17	Moderate
Apr	18	Moderate
May	17	Moderate
Jun	16	Moderate
Jul	13	Moderate
Aug	12	Good
Sep	10	Good
Oct	10	Good
Nov	9	Good
Dec	8	Good

Location & terrain

Where is Tōmi?

Tōmi sits at 36.4°N, 138.4°E, 639 m above sea level, in Japan. The nearest listed city is Komoro, 8.0 km away.

Topography around Tōmi

How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Tōmi.

Within 3 km, the terrain around Tōmi has significant variations in elevation — a maximum elevation change of 474 m around an average of 661 m above sea level; within 16 km, very significant variations in elevation — a maximum elevation change of 2,148 m; within 80 km, extreme variations in elevation — a maximum elevation change of 3,154 m.

The land around Tōmi is covered by trees (32%), artificial surfaces (28%) and cropland (25%) within 3 km, trees (61%) within 16 km, and trees (83%) within 80 km.

3 km

474 m

trees 32%

16 km

2,148 m

trees 61%

80 km

3,154 m

trees 83%

treesgrasslandcroplandartificial surfacesbare terrainwater

← April Tōmi year-round climate June →Best places to visit in May

May weather nearby: Komoro 8.0 km · Ueda 9.0 km · Kamimaruko 9.0 km · Miyota 14 km · Saku 19 km · Sakaki 20 km · Karuizawa 24 km · Chikuma 31 km

Japan travel facts

Travel advisory: Level 1; Exercise Normal Precautions
Power plugs: Type A / B; 100 V · 50 / 60 Hz
Prices: ≈ 65% of US; price level, 2025
GDP per capita: $35,951; 2025
Happiness: 6.1 / 10; World Happiness, 2025
Safe drinking water: 99%; of population, 2024
Homicide rate: 0.2; per 100k, 2023
Road deaths: 3.6; per 100k/yr, 2019
Income group: High; World Bank
English: Very low; EF EPI 446
Religion

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 Tōmi (36.3558°, 138.3609°, elevation 639 m), 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).

	Avg high (°C)	Avg low (°C)
1	18	7
2	18	7
3	18	7
4	18	7
5	18	8
6	19	8
7	19	8
8	19	8
9	19	8
10	19	8
11	19	9
12	19	9
13	19	9
14	20	9
15	20	9
16	20	9
17	20	9
18	20	10
19	20	10
20	20	10
21	20	10
22	21	10
23	21	10
24	21	11
25	21	11
26	21	11
27	21	11
28	21	11
29	21	11
30	21	12
31	22	12

	Clearer (%)	Cloudier (%)
1	48	52
2	47	53
3	46	54
4	47	53
5	46	54
6	46	54
7	45	55
8	44	56
9	44	56
10	43	57
11	42	58
12	43	57
13	42	58
14	42	58
15	42	58
16	42	58
17	42	58
18	41	59
19	41	59
20	41	59
21	41	59
22	40	60
23	40	60
24	40	60
25	39	61
26	38	62
27	38	62
28	37	63
29	37	63
30	35	65
31	34	66

	Rain chance (%)
1	33
2	32
3	32
4	33
5	33
6	33
7	34
8	34
9	35
10	35
11	35
12	36
13	36
14	36
15	37
16	37
17	37
18	37
19	36
20	36
21	36
22	36
23	36
24	36
25	35
26	35
27	35
28	34
29	34
30	34
31	35

	Dry (%)	Comfortable (%)
1	99	1
2	98	2
3	98	2
4	98	2
5	98	2
6	98	2
7	98	2
8	97	3
9	97	3
10	97	3
11	97	3
12	97	3
13	96	4
14	96	4
15	96	4
16	96	4
17	96	4
18	96	4
19	96	4
20	96	4
21	96	4
22	95	5
23	95	5
24	95	5
25	95	5
26	95	5
27	95	5
28	94	6
29	94	6
30	93	7
31	92	8

	Avg high (°C)	Avg low (°C)
1	18	7
2	18	7
3	18	7
4	18	7
5	18	8
6	19	8
7	19	8
8	19	8
9	19	8
10	19	8
11	19	9
12	19	9
13	19	9
14	20	9
15	20	9
16	20	9
17	20	9
18	20	10
19	20	10
20	20	10
21	20	10
22	21	10
23	21	10
24	21	11
25	21	11
26	21	11
27	21	11
28	21	11
29	21	11
30	21	12
31	22	12

	Clearer (%)	Cloudier (%)
1	48	52
2	47	53
3	46	54
4	47	53
5	46	54
6	46	54
7	45	55
8	44	56
9	44	56
10	43	57
11	42	58
12	43	57
13	42	58
14	42	58
15	42	58
16	42	58
17	42	58
18	41	59
19	41	59
20	41	59
21	41	59
22	40	60
23	40	60
24	40	60
25	39	61
26	38	62
27	38	62
28	37	63
29	37	63
30	35	65
31	34	66

	Rain chance (%)
1	33
2	32
3	32
4	33
5	33
6	33
7	34
8	34
9	35
10	35
11	35
12	36
13	36
14	36
15	37
16	37
17	37
18	37
19	36
20	36
21	36
22	36
23	36
24	36
25	35
26	35
27	35
28	34
29	34
30	34
31	35

	Dry (%)	Comfortable (%)
1	99	1
2	98	2
3	98	2
4	98	2
5	98	2
6	98	2
7	98	2
8	97	3
9	97	3
10	97	3
11	97	3
12	97	3
13	96	4
14	96	4
15	96	4
16	96	4
17	96	4
18	96	4
19	96	4
20	96	4
21	96	4
22	95	5
23	95	5
24	95	5
25	95	5
26	95	5
27	95	5
28	94	6
29	94	6
30	93	7
31	92	8

	Avg high (°C)	Avg low (°C)
1	18	7
2	18	7
3	18	7
4	18	7
5	18	8
6	19	8
7	19	8
8	19	8
9	19	8
10	19	8
11	19	9
12	19	9
13	19	9
14	20	9
15	20	9
16	20	9
17	20	9
18	20	10
19	20	10
20	20	10
21	20	10
22	21	10
23	21	10
24	21	11
25	21	11
26	21	11
27	21	11
28	21	11
29	21	11
30	21	12
31	22	12

	Clearer (%)	Cloudier (%)
1	48	52
2	47	53
3	46	54
4	47	53
5	46	54
6	46	54
7	45	55
8	44	56
9	44	56
10	43	57
11	42	58
12	43	57
13	42	58
14	42	58
15	42	58
16	42	58
17	42	58
18	41	59
19	41	59
20	41	59
21	41	59
22	40	60
23	40	60
24	40	60
25	39	61
26	38	62
27	38	62
28	37	63
29	37	63
30	35	65
31	34	66

	Rain chance (%)
1	33
2	32
3	32
4	33
5	33
6	33
7	34
8	34
9	35
10	35
11	35
12	36
13	36
14	36
15	37
16	37
17	37
18	37
19	36
20	36
21	36
22	36
23	36
24	36
25	35
26	35
27	35
28	34
29	34
30	34
31	35

	Dry (%)	Comfortable (%)
1	99	1
2	98	2
3	98	2
4	98	2
5	98	2
6	98	2
7	98	2
8	97	3
9	97	3
10	97	3
11	97	3
12	97	3
13	96	4
14	96	4
15	96	4
16	96	4
17	96	4
18	96	4
19	96	4
20	96	4
21	96	4
22	95	5
23	95	5
24	95	5
25	95	5
26	95	5
27	95	5
28	94	6
29	94	6
30	93	7
31	92	8