Unnan weather in December

In December, Unnan sees average daytime highs of 9°C and overnight lows near 2°C, with 114 mm of precipitation across 16.3 wet days and about 9.7 hours of daylight. It is the 10th-warmest and 9th-wettest month of the year here.

Highs ease over the month, from about 11°C in the first days to 8°C by the end. The sky is clear or mostly clear about 13% of the time in December, and the air most often feels dry.

Daylight stretches from about 9 h 48 min at the start of December to 9 h 42 min by month's end. Set against the rest of the year, December is Unnan's 7th-clearest and 2nd-windiest month. For the whole year in context, see Unnan's year-round climate.

Daytime high
10th warmest
Overnight low
3rd coldest
Precipitation
114 mm
16.3 wet days
Daylight
9 h 36 min
7:15 AM – 4:54 PM
Cloud cover
65%
7th clearest
Wind
12 km/h
2nd windiest
Solar energy
2.07 kWh/m²
Travel score
1.6
out of 10

Temperature in December

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 11°C in the first days to 8°C by the end.

A typical December day in Unnan reaches about 9°C in the afternoon and slips back to 2°C overnight — a 7°C spread between the day's warmth and the night's chill. On most days the high lands between 4°C and 13°C. Set against its neighbours, December runs about 6°C cooler than November and about 3°C warmer than January.

-5°10°15°20°151015202531
Avg high (°C)Avg low (°C)
1124
2124
3114
4114
5114
6114
7103
8103
9103
10103
11103
12103
1393
1493
1592
1692
1792
1892
1992
2092
2182
2282
2382
2482
2582
2681
2781
2881
2981
3081
3181

How December really feels in Unnan

Once humidity and wind are folded in, December averages 0 days that feel above 32°C and 22 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
22
wind chill below the day's low

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

Unnan 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 / 1071710.39.90.6
Feb / 10014.88.410.71.0
Mar12° / 12814.93.211.72.7
Apr17° / 11711.40.212.95.3
May22° / 13°12811013.86.4
Jun25° / 18°17514.4014.35.8
Jul29° / 22°22916.6014.14.6
Aug30° / 23°16115.1013.34.4
Sep26° / 18°21314.1012.25.9
Oct20° / 12°11610.6011.16.3
Nov15° / 9411.20.310.14.3
Dec / 11416.36.19.71.6

Cloud cover in December

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 13% of the time in December.

Beyond those clear spells, partly cloudy skies cover about 24% of December, with mostly cloudy or overcast conditions the remaining 62%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14258
24258
34258
44159
54258
64060
74060
84060
94060
103961
113961
123961
133763
143763
153763
163664
173664
183664
193664
203664
213565
223664
233664
243664
253664
263664
273664
283664
293664
303763
313664

Chance of precipitation in December

Any precipitationSnow

Unnan gets around 114 mm of rain and snow over 16.3 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 52% and peaks near 55% on the wettest days, and about 6 days bring snow. The odds climb toward the end of the month.

0%20%40%60%151015202531
Rain chance (%)Snow chance (%)
1457
2467
3478
4479
54810
64911
75012
85114
95215
105216
115317
125318
135418
145419
155420
165420
175521
185521
195522
205523
215523
225424
235425
245425
255425
265326
275326
285327
295327
305327
315228

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 (%)Comfortable (%)
1991
2991
3991
4991
51000
61000
71000
81000
91000
101000
111000
121000
131000
141000
151000
161000
171000
181000
191000
201000
211000
221000
231000
241000
251000
261000
271000
281000
291000
301000
311000

Wind in December

Winds average 12 km/h in December.

Across December, daily wind ranges from about 11 km/h on the calmest days to 12 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (km/h)Feels
111calm
211calm
311calm
411calm
511calm
612calm
712calm
812calm
912calm
1012calm
1112calm
1212calm
1312calm
1412calm
1512calm
1612calm
1712light breeze
1812light breeze
1912light breeze
2012light breeze
2112light breeze
2212light breeze
2312light breeze
2412light breeze
2512light breeze
2612light breeze
2712light breeze
2812light breeze
2912light breeze
3012light breeze
3112light breeze

Sunrise & sunset in December

DaylightNight

Daylight runs from about 9 h 48 min at the start of December to 9 h 42 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 7:04 AM to 7:22 AM, and sunset from 4:52 PM to 5:01 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
19.87:044:52
29.87:054:52
39.87:064:52
49.87:074:52
59.77:084:52
69.77:084:52
79.77:094:52
89.77:104:52
99.77:114:52
109.77:114:52
119.77:124:52
129.77:134:53
139.77:144:53
149.67:144:53
159.67:154:53
169.67:154:54
179.67:164:54
189.67:174:54
199.67:174:55
209.67:184:55
219.67:184:56
229.67:194:56
239.67:194:56
249.67:204:57
259.67:204:58
269.67:204:58
279.67:214:59
289.67:214:59
299.67:215:00
309.67:225:01
319.77:225:01

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 2.07 kWh/m² — the year's lowest.

For context, solar energy here swings from a low near 2.07 kWh/m² to a high of 5.72 kWh/m² in May across the year — December's 2.07 kWh/m² sits near the bottom.

0123151015202531
Solar energy (kWh/m²)Level
12.2Moderate
22.1Moderate
32.1Moderate
42.1Moderate
52.1Moderate
62.1Moderate
72.1Moderate
82.1Moderate
92.1Moderate
102.1Moderate
112.1Moderate
122.1Moderate
132.1Moderate
142.1Moderate
152.1Moderate
162.1Moderate
172.1Moderate
182.1Moderate
192.1Moderate
202.1Moderate
212.1Moderate
222.1Moderate
232.1Moderate
242.1Moderate
252.1Moderate
262.1Moderate
272.1Moderate
282.2Moderate
292.2Moderate
302.2Moderate
312.2Moderate
Planning a trip in December

Hazard calendar for Unnan

In seasonPeak

In December, Unnan sits inside its pacific typhoon season. The full year is below, with each hazard's peak months called out.

Unnan sits in the Pacific typhoon belt; the season peaks July–October.

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

Is December a good time to visit Unnan?

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

1.6
Sightseeing
10th-best month of the year
0.0
Beach & pool
10th-best month of the year

December is a weaker month for outdoor sightseeing in Unnan.

What to pack for Unnan in December

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

In December, Unnan sees daytime highs around 9°C and nights near 2°C. Pack a warm layer and rain gear. About 16 days see rain.

a warm layerrain gear

Sea temperature near Unnan in December

The nearest coast averages about 17°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 29 km away) is warmest in August at about 27°C and coldest in February near 13°C.

It's comfortable for a long swim from Jun 12 to Nov 15 — about 5.2 months when the water holds above 20°C.

10°15°20°25°30°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan15Bracing
Feb13Bracing
Mar13Bracing
Apr15Bracing
May17Cool
Jun21Refreshing
Jul24Warm
Aug27Warm
Sep25Warm
Oct23Refreshing
Nov20Refreshing
Dec17Cool

UV index in Unnan 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 Unnan peaks around July 18 at about 10 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 23 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 18UV 10Dec 23UV 2
UV index (midday)Level
Jan3Moderate
Feb4Moderate
Mar5High
Apr7Very high
May8Very high
Jun9Very high
Jul11Extreme
Aug10Very high
Sep9Very high
Oct6High
Nov4Moderate
Dec2Moderate

Air quality in Unnan 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 Unnan is worst in April — around 22 µg/m³ PM2.5 (moderate), about 2.3× the cleanest month (October, 10 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodApr 1222 µg/m³Oct 1310 µg/m³
PM2.5 (µg/m³)Level
Jan14Moderate
Feb16Moderate
Mar21Moderate
Apr22Moderate
May20Moderate
Jun17Moderate
Jul13Moderate
Aug12Good
Sep11Good
Oct10Good
Nov12Good
Dec11Good
Location & terrain

Where is Unnan?

Unnan sits at 35.2°N, 132.9°E, 82 m above sea level, in Japan. The nearest listed city is Izumo, 18 km away.

Topography around Unnan

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

Within 3 km, the terrain around Unnan has significant variations in elevation — a maximum elevation change of 398 m around an average of 240 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 1,049 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,623 m.

The land around Unnan is covered by trees (94%) within 3 km, trees (92%) within 16 km, and trees (60%) and water (35%) within 80 km.

3 km
398 m
16 km
1,049 m
80 km
1,623 m
treesgrasslandcroplandartificial surfaceswater
December weather nearby: Izumo 18 km · Hiratachō 22 km · Matsue 30 km · Ōdachō-ōda 36 km · Yasugichō 37 km · Sakaiminato 44 km · Yonago 45 km · Shōbara 45 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 Unnan (35.2431°, 132.8999°, elevation 82 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. Tropical-cyclone seasons are the published climatological basin seasons (NOAA National Hurricane Center / regional warning centres). 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).