Komoro weather in December

In December, Komoro sees average daytime highs of 6°C and overnight lows near -2°C, with 48 mm of precipitation across 7.9 wet days and about 9.6 hours of daylight. It is the 10th-warmest and 12th-wettest month of the year here.

Highs ease over the month, from about 8°C in the first days to 4°C by the end. The sky is clear or mostly clear about 43% 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 36 min by month's end. Set against the rest of the year, December is Komoro's 1st-clearest and 5th-windiest month. For the whole year in context, see Komoro's year-round climate.

Daytime high
10th warmest
Overnight low
-2°
3rd coldest
Precipitation
48 mm
7.9 wet days
Daylight
9 h 30 min
6:56 AM – 4:29 PM
Cloud cover
48%
1st clearest
Wind
7 km/h
5th windiest
Solar energy
2.52 kWh/m²
Travel score
0.4
out of 10

Komoro is city in Nagano Prefecture, Japan.

Density
470/km²
people per km²
Founded
1954

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

Temperature in December

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 8°C in the first days to 4°C by the end.

A typical December day in Komoro reaches about 6°C in the afternoon and slips back to -2°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 10°C. Set against its neighbours, December runs about 6°C cooler than November and about 3°C warmer than January.

-10°-5°10°15°151015202531
Avg high (°C)Avg low (°C)
180
280
380
480
57-1
67-1
77-1
87-1
97-1
106-1
116-1
126-2
136-2
146-2
156-2
165-2
175-2
185-2
195-3
205-3
215-3
225-3
234-3
244-3
254-3
264-3
274-3
284-4
294-4
304-4
314-4

How December really feels in Komoro

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.

Komoro weather by month

How December compares with the rest of the year at a glance. December is the 10th-warmest and 12th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan / -5°557.57.89.80.0
Feb / -5°5787.110.60.0
Mar / -2°9911.77.311.71.3
Apr14° / 10212.32.312.93.9
May19° / 131150.113.95.4
Jun22° / 14°19719.8014.44.8
Jul26° / 18°22021.6014.24.8
Aug27° / 19°17421.6013.44.8
Sep23° / 15°18717.6012.25.3
Oct17° / 16112.9011.15.0
Nov11° / 647.80.610.13.0
Dec / -2°487.95.39.60.4

Cloud cover in December

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 43% of the time in December, the clearest month of the year.

Beyond those clear spells, partly cloudy skies cover about 23% of December, with mostly cloudy or overcast conditions the remaining 34%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
16337
26238
36337
46337
56337
66337
76436
86436
96436
106535
116535
126535
136535
146535
156535
166535
176634
186634
196733
206733
216733
226733
236832
246832
256832
266832
276931
286931
296931
306931
316931

Chance of precipitation in December

Any precipitationSnow

Komoro gets around 48 mm of rain and snow over 7.9 wet days in December, the driest month. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable precipitation averages around 25% and peaks near 26% on the wettest days, and about 5 days bring snow.

0%10%20%30%40%151015202531
Rain chance (%)Snow chance (%)
1259
22510
32510
42611
52611
62612
72613
82613
92614
102614
112514
122515
132515
142515
152515
162416
172416
182417
192417
202418
212418
222419
232419
242420
252420
262420
272421
282421
292421
302421
312422

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
106calm
116calm
126calm
136calm
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 36 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 6 minutes over December. Sunrise moves from 6:45 AM to 7:03 AM, and sunset from 4:27 PM to 4:36 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
19.76:454:27
29.76:464:27
39.76:474:27
49.76:474:27
59.66:484:27
69.66:494:27
79.66:504:27
89.66:514:27
99.66:514:27
109.66:524:27
119.66:534:27
129.66:544:28
139.66:544:28
149.56:554:28
159.56:564:28
169.56:564:29
179.56:574:29
189.56:574:29
199.56:584:30
209.56:594:30
219.56:594:30
229.57:004:31
239.57:004:31
249.57:004:32
259.57:014:32
269.57:014:33
279.57:024:34
289.57:024:34
299.57:024:35
309.57:024:35
319.67:034:36

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 2.52 kWh/m² — the year's lowest.

For context, solar energy here swings from a low near 2.52 kWh/m² to a high of 5.67 kWh/m² in May across the year — December's 2.52 kWh/m² sits near the bottom.

0123151015202531
Solar energy (kWh/m²)Level
12.5Moderate
22.5Moderate
32.5Moderate
42.5Moderate
52.5Moderate
62.5Moderate
72.5Moderate
82.5Moderate
92.5Moderate
102.5Moderate
112.5Moderate
122.5Moderate
132.5Moderate
142.5Moderate
152.5Moderate
162.5Moderate
172.5Moderate
182.5Moderate
192.5Moderate
202.6Moderate
212.6Moderate
222.6Moderate
232.6Moderate
242.6Moderate
252.6Moderate
262.6Moderate
272.7Moderate
282.7Moderate
292.7Moderate
302.7Moderate
312.7Moderate
Planning a trip in December

Hazard calendar for Komoro

In seasonPeak

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

Komoro's rainy season runs April–October, when most of the year's rain falls.

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

Is December a good time to visit Komoro?

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

0.4
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 Komoro.

What to pack for Komoro in December

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

In December, Komoro sees daytime highs around 6°C and nights near -2°C. Pack a warm layer. Worth having: a heavy coat. About 8 days see rain.

a warm layera heavy coat

UV index in Komoro 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 Komoro 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.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highModerateJul 18UV 10Dec 22UV 2
UV index (midday)Level
Jan3Moderate
Feb4Moderate
Mar5High
Apr7Very high
May9Very high
Jun10Very high
Jul10Very high
Aug10Very high
Sep9Very high
Oct6High
Nov3Moderate
Dec2Moderate

Air quality in Komoro 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 Komoro 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 1821 µg/m³Dec 1810 µg/m³
PM2.5 (µg/m³)Level
Jan11Good
Feb14Moderate
Mar19Moderate
Apr21Moderate
May20Moderate
Jun18Moderate
Jul15Moderate
Aug14Moderate
Sep13Moderate
Oct12Moderate
Nov11Good
Dec10Good
Location & terrain

Where is Komoro?

Komoro sits at 36.3°N, 138.4°E, 686 m above sea level, in Japan. The nearest listed city is Miyota, 7.0 km away.

Topography around Komoro

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

Within 3 km, the terrain around Komoro has significant variations in elevation — a maximum elevation change of 393 m around an average of 720 m above sea level; within 16 km, very significant variations in elevation — a maximum elevation change of 2,103 m; within 80 km, extreme variations in elevation — a maximum elevation change of 3,141 m.

The land around Komoro is covered by artificial surfaces (33%), trees (31%) and cropland (23%) within 3 km, trees (63%) within 16 km, and trees (82%) within 80 km.

3 km
393 m
16 km
2,103 m
80 km
3,141 m
treesgrasslandcroplandartificial surfacesbare terrainwater
December weather nearby: Miyota 7.0 km · Tōmi 8.0 km · Saku 12 km · Kamimaruko 14 km · Ueda 17 km · Karuizawa 18 km · Sakaki 28 km · Suzaka 38 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 Komoro (36.3167°, 138.4333°, elevation 686 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).