Chikuma weather in December

In December, Chikuma sees average daytime highs of 4°C and overnight lows near -4°C, with 155 mm of precipitation across 19.7 wet days and about 9.6 hours of daylight. It is the 10th-warmest and 9th-wettest month of the year here.

Highs ease over the month, from about 6°C in the first days to 2°C by the end. The sky is clear or mostly clear about 22% of the time in December, and the air most often feels dry.

Daylight stretches from about 9 h 42 min at the start of December to 9 h 30 min by month's end. Set against the rest of the year, December is Chikuma's 4th-clearest and 4th-windiest month. For the whole year in context, see Chikuma's year-round climate.

Daytime high
10th warmest
Overnight low
-4°
3rd coldest
Precipitation
155 mm
19.7 wet days
Daylight
9 h 30 min
6:58 AM – 4:29 PM
Cloud cover
61%
4th clearest
Wind
7 km/h
4th windiest
Solar energy
2.27 kWh/m²
Travel score
0.1
out of 10

Temperature in December

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 6°C in the first days to 2°C by the end.

A typical December day in Chikuma reaches about 4°C in the afternoon and slips back to -4°C overnight — a 8°C spread between the day's warmth and the night's chill. On most days the high lands between -1°C and 8°C. Set against its neighbours, December runs about 7°C cooler than November and about 3°C warmer than January.

-10°10°151015202531
Avg high (°C)Avg low (°C)
17-2
27-2
36-2
46-2
56-2
66-3
75-3
85-3
95-3
105-3
114-4
124-4
134-4
144-4
154-4
163-4
173-5
183-5
193-5
203-5
213-5
223-5
232-5
242-5
252-5
262-6
272-6
282-6
292-6
302-6
311-6

How December really feels in Chikuma

Once humidity and wind are folded in, December averages 0 days that feel above 32°C and 31 that feel at or below 0°C — the comfort signal a plain temperature reading hides.

Days feeling ≥ 32°C
0
heat index over the day's high
Days feeling ≤ C
31
wind chill below the day's low

The story in December is cold — wind chill drags the overnight "feels like" below the raw low.

Chikuma weather by month

How December compares with the rest of the year at a glance. December is the 10th-warmest and 9th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan / -7°15220.121.79.80.0
Feb / -6°12916.716.910.60.0
Mar / -3°18017.814.111.70.5
Apr13° / 15815.53.912.93.1
May19° / 19316.40.113.95.1
Jun22° / 14°28820.6014.44.7
Jul25° / 18°33823.2014.24.6
Aug27° / 18°22519.7013.45.1
Sep23° / 14°25619012.25.1
Oct17° / 22318.50.211.14.3
Nov10° / 14916.85.310.12.1
Dec / -4°15519.717.39.60.1

Cloud cover in December

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 22% of the time in December.

Beyond those clear spells, partly cloudy skies cover about 21% of December, with mostly cloudy or overcast conditions the remaining 57%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14654
24456
34456
44456
54456
64357
74357
84357
94357
104258
114159
124159
134159
144258
154258
164357
174357
184258
194258
204357
214456
224357
234357
244357
254456
264555
274456
284456
294456
304456
314357

Chance of precipitation in December

Any precipitationSnow

Chikuma gets around 155 mm of rain and snow over 19.7 wet days in December. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable precipitation averages around 63% and peaks near 64% on the wettest days, and about 17 days bring snow.

0%20%40%60%80%151015202531
Rain chance (%)Snow chance (%)
16137
26239
36241
46343
56345
66446
76448
86450
96451
106453
116454
126455
136455
146456
156456
166357
176357
186358
196358
206359
216359
226360
236360
246361
256362
266363
276363
286364
296365
306366
316366

Humidity in December

DryComfortableHumidMuggyOppressiveMiserable

Most of December feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, December 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 (%)
1100
2100
3100
4100
5100
6100
7100
8100
9100
10100
11100
12100
13100
14100
15100
16100
17100
18100
19100
20100
21100
22100
23100
24100
25100
26100
27100
28100
29100
30100
31100

Wind in December

Winds average 7 km/h in December.

Across December, daily wind ranges from about 6 km/h on the calmest days to 7 km/h at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (km/h)Feels
16calm
26calm
36calm
46calm
56calm
66calm
76calm
86calm
96calm
107calm
117calm
127calm
137calm
147calm
157calm
167calm
177calm
187calm
197calm
207calm
217calm
227calm
237calm
247calm
257calm
267calm
277calm
287calm
297calm
307calm
317calm

Sunrise & sunset in December

DaylightNight

Daylight runs from about 9 h 42 min at the start of December to 9 h 30 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 12 minutes over December. Sunrise moves from 6:47 AM to 7:05 AM, and sunset from 4:28 PM to 4:37 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
19.76:474:28
29.76:484:28
39.76:494:28
49.66:494:28
59.66:504:28
69.66:514:28
79.66:524:28
89.66:534:28
99.66:534:28
109.66:544:28
119.66:554:28
129.56:564:28
139.56:564:29
149.56:574:29
159.56:584:29
169.56:584:29
179.56:594:30
189.56:594:30
199.57:004:30
209.57:014:31
219.57:014:31
229.57:024:32
239.57:024:32
249.57:024:33
259.57:034:33
269.57:034:34
279.57:044:34
289.57:044:35
299.57:044:36
309.57:044:36
319.57:054:37

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 2.27 kWh/m² — the year's lowest.

For context, solar energy here swings from a low near 2.27 kWh/m² to a high of 5.7 kWh/m² in May across the year — December's 2.27 kWh/m² sits near the bottom.

0123151015202531
Solar energy (kWh/m²)Level
12.3Moderate
22.3Moderate
32.3Moderate
42.3Moderate
52.3Moderate
62.3Moderate
72.3Moderate
82.3Moderate
92.3Moderate
102.3Moderate
112.3Moderate
122.3Moderate
132.3Moderate
142.3Moderate
152.3Moderate
162.3Moderate
172.3Moderate
182.3Moderate
192.3Moderate
202.3Moderate
212.3Moderate
222.3Moderate
232.3Moderate
242.3Moderate
252.3Moderate
262.4Moderate
272.4Moderate
282.4Moderate
292.4Moderate
302.4Moderate
312.4Moderate
Planning a trip in December

Is December a good time to visit Chikuma?

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

0.1
Sightseeing
10th-best month of the year
0.0
Beach & pool
9th-best month of the year

December is a weaker month for outdoor sightseeing in Chikuma.

What to pack for Chikuma in December

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

In December, Chikuma sees daytime highs around 4°C and nights near -4°C. Pack a warm layer, a heavy coat and rain gear. About 20 days see rain.

a warm layera heavy coatrain gear

Sea temperature near Chikuma in December

The nearest coast averages about 15°C in December — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 67 km away) is warmest in August at about 27°C and coldest in March near 10°C.

It's comfortable for a long swim from Jun 20 to Nov 1 — about 4.4 months when the water holds above 20°C.

10°20°30°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan13Bracing
Feb11Bracing
Mar10Bracing
Apr11Bracing
May15Bracing
Jun20Cool
Jul23Refreshing
Aug27Warm
Sep25Warm
Oct22Refreshing
Nov19Cool
Dec15Cool

UV index in Chikuma in December

LowModerateHighVery highExtreme

Clear-sky midday UV in December peaks around 2. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Chikuma peaks around July 20 at about 10 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 21 at about 2 (moderate).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highExtremeVery highModerateJul 20UV 10Dec 21UV 2
UV index (midday)Level
Jan3Moderate
Feb5Moderate
Mar6High
Apr7Very high
May9Very high
Jun10Very high
Jul10Extreme
Aug10Extreme
Sep9Very high
Oct6High
Nov3Moderate
Dec2Moderate

Air quality in Chikuma in December

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where December falls, not just the annual average.

Air quality in Chikuma is worst in April — around 21 µg/m³ PM2.5 (moderate), about 2.2× the cleanest month (December, 10 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodApr 1721 µg/m³Dec 1510 µg/m³
PM2.5 (µg/m³)Level
Jan11Good
Feb14Moderate
Mar20Moderate
Apr21Moderate
May20Moderate
Jun18Moderate
Jul15Moderate
Aug13Moderate
Sep12Good
Oct11Good
Nov11Good
Dec10Good
Location & terrain

Where is Chikuma?

Chikuma sits at 36.5°N, 138.1°E, 388 m above sea level, in Japan. The nearest listed city is Sakaki, 11 km away.

Topography around Chikuma

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

Within 3 km, the terrain around Chikuma has large variations in elevation — a maximum elevation change of 635 m around an average of 539 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 1,102 m; within 80 km, extreme variations in elevation — a maximum elevation change of 3,130 m.

The land around Chikuma is covered by trees (54%) and artificial surfaces (22%) within 3 km, trees (78%) within 16 km, and trees (78%) within 80 km.

3 km
635 m
16 km
1,102 m
80 km
3,130 m
treesgrasslandcroplandartificial surfaceswater
December weather nearby: Sakaki 11 km · Nagano 16 km · Ōmachi 20 km · Ueda 22 km · Suzaka 24 km · Hotaka 28 km · Kamimaruko 28 km · Toyoshina 30 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
Shintoism 49%Buddhism 46%other 4%Christianity 1%

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 Chikuma (36.5271°, 138.0894°, elevation 388 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. 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).