Iki weather in December

In December, Iki sees average daytime highs of 13°C and overnight lows near 10°C, with 79 mm of precipitation across 11 wet days and about 9.8 hours of daylight. It is the 10th-warmest and 10th-wettest month of the year here.

Highs ease over the month, from about 14°C in the first days to 11°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 54 min at the start of December to 9 h 48 min by month's end. Set against the rest of the year, December is Iki's 8th-clearest and 2nd-windiest month. For the whole year in context, see Iki's year-round climate.

Daytime high
13°
10th warmest
Overnight low
10°
3rd coldest
Precipitation
79 mm
11 wet days
Daylight
9 h 48 min
7:24 AM – 5:10 PM
Cloud cover
64%
8th clearest
Wind
26 km/h
2nd windiest
Solar energy
2.19 kWh/m²
Travel score
3.4
out of 10

Temperature in December

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 14°C in the first days to 11°C by the end.

A typical December day in Iki reaches about 13°C in the afternoon and slips back to 10°C overnight — a 3°C spread between the day's warmth and the night's chill. On most days the high lands between 9°C and 16°C. Set against its neighbours, December runs about 5°C cooler than November and about 3°C warmer than January.

10°15°20°151015202531
Avg high (°C)Avg low (°C)
11512
21512
31412
41411
51411
61411
71411
81411
91311
101310
111310
121310
131310
141310
151310
161210
171210
181210
19129
20129
21129
22129
23129
24129
25129
26129
27129
28119
29119
30118
31118

How December really feels in Iki

Once humidity and wind are folded in, December 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
0
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

December sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Iki weather by month

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

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan10° / 7811.90.5102.2
Feb11° / 7810.20.410.72.4
Mar13° / 10°12611.2011.73.4
Apr16° / 14°13410.1012.84.9
May19° / 17°1389.5013.76.1
Jun22° / 21°25112.6014.25.9
Jul26° / 24°24312.90146.2
Aug27° / 26°15811.2013.36.3
Sep25° / 24°17111.2012.26.6
Oct21° / 20°1007.6011.17.1
Nov17° / 15°979.2010.25.7
Dec13° / 10°79110.29.83.4

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 18% of December, with mostly cloudy or overcast conditions the remaining 60%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14555
24456
34555
44456
54357
64258
74159
84159
94060
103961
113961
123961
133862
143862
153862
163961
173862
183862
193961
203862
213961
223961
234060
244060
254060
264159
274159
284060
294060
304060
313961

Chance of precipitation in December

Any precipitation

Iki gets around 79 mm of rain and snow over 11 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 35% and peaks near 36% on the wettest days, and about 0 day brings snow.

0%10%20%30%40%50%151015202531
Rain chance (%)
134
235
335
435
535
635
735
835
935
1035
1135
1236
1336
1435
1535
1635
1735
1835
1935
2035
2135
2235
2335
2436
2536
2636
2736
2835
2935
3035
3135

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 98% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)
19541
29541
39541
49631
59631
69631
79721
89721
99820
109820
119820
129820
139820
149820
159820
169910
179910
189910
199910
209910
219910
229910
239910
249910
259910
2610000
2710000
2810000
2910000
3010000
3110000

Wind in December

Winds average 26 km/h in December.

Across December, daily wind ranges from about 25 km/h on the calmest days to 27 km/h at its breeziest. It stays fairly steady from day to day.

0102030151015202531
Wind speed (km/h)Feels
125breezy
225breezy
325breezy
425breezy
525breezy
625breezy
725breezy
825breezy
925breezy
1025breezy
1126breezy
1226breezy
1326breezy
1426breezy
1526breezy
1626breezy
1726breezy
1826breezy
1926breezy
2026breezy
2126breezy
2226breezy
2326breezy
2427breezy
2527breezy
2627breezy
2727breezy
2827breezy
2927breezy
3027breezy
3127breezy

Sunrise & sunset in December

DaylightNight

Daylight runs from about 9 h 54 min at the start of December to 9 h 48 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 7:13 AM to 7:31 AM, and sunset from 5:08 PM to 5:18 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
19.97:135:08
29.97:145:08
39.97:155:08
49.97:165:08
59.97:175:08
69.87:175:08
79.87:185:08
89.87:195:08
99.87:205:09
109.87:205:09
119.87:215:09
129.87:225:09
139.87:225:09
149.87:235:10
159.87:245:10
169.87:245:10
179.87:255:11
189.87:255:11
199.87:265:11
209.87:275:12
219.87:275:12
229.87:285:13
239.87:285:13
249.87:285:14
259.87:295:14
269.87:295:15
279.87:305:15
289.87:305:16
299.87:305:16
309.87:315:17
319.87:315:18

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 2.19 kWh/m² — the year's lowest.

For context, solar energy here swings from a low near 2.19 kWh/m² to a high of 5.6 kWh/m² in May across the year — December's 2.19 kWh/m² sits near the bottom.

0123151015202531
Solar energy (kWh/m²)Level
12.3Moderate
22.3Moderate
32.3Moderate
42.3Moderate
52.3Moderate
62.2Moderate
72.2Moderate
82.2Moderate
92.2Moderate
102.2Moderate
112.2Moderate
122.2Moderate
132.2Moderate
142.2Moderate
152.2Moderate
162.2Moderate
172.2Moderate
182.2Moderate
192.2Moderate
202.2Moderate
212.2Moderate
222.2Moderate
232.2Moderate
242.2Moderate
252.2Moderate
262.2Moderate
272.2Moderate
282.2Moderate
292.3Moderate
302.3Moderate
312.3Moderate
Planning a trip in December

Hazard calendar for Iki

In seasonPeak

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

Iki 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 Iki?

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

3.4
Sightseeing
9th-best month of the year
0.0
Beach & pool
9th-best month of the year

December is a weaker month for outdoor sightseeing in Iki.

What to pack for Iki in December

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

In December, Iki sees daytime highs around 13°C and nights near 10°C. Worth packing: a warm layer, rain gear and a windbreaker. About 11 days see rain.

a warm layerrain geara windbreaker

Sea temperature near Iki in December

The nearest coast averages about 18°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 14 km away) is warmest in August at about 27°C and coldest in February near 15°C.

It's comfortable for a long swim from Jun 6 to Nov 26 — about 5.7 months when the water holds above 20°C.

15°20°25°30°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan16Cool
Feb15Bracing
Mar15Bracing
Apr16Cool
May18Cool
Jun21Refreshing
Jul25Warm
Aug27Warm
Sep26Warm
Oct23Refreshing
Nov21Refreshing
Dec18Cool

UV index in Iki in December

LowModerateHighVery highExtreme

Clear-sky midday UV in December peaks around 3. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Iki peaks around July 23 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 22 at about 3 (moderate).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highModerateJul 23UV 9Dec 22UV 3
UV index (midday)Level
Jan3Moderate
Feb4Moderate
Mar6High
Apr8Very high
May8Very high
Jun8Very high
Jul9Very high
Aug9Very high
Sep9Very high
Oct6High
Nov4Moderate
Dec3Moderate

Air quality in Iki 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 Iki is worst in April — around 24 µg/m³ PM2.5 (moderate), about 2.2× the cleanest month (July, 11 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodModerateApr 924 µg/m³Jul 2211 µg/m³
PM2.5 (µg/m³)Level
Jan17Moderate
Feb20Moderate
Mar24Moderate
Apr24Moderate
May21Moderate
Jun16Moderate
Jul11Good
Aug11Good
Sep12Good
Oct11Good
Nov14Moderate
Dec13Moderate
Location & terrain

Where is Iki?

Iki sits at 33.8°N, 129.7°E, 45 m above sea level, in Japan. The nearest listed city is Karatsu, 44 km away.

Topography around Iki

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

Within 3 km, the terrain around Iki has only modest variations in elevation — a maximum elevation change of 152 m around an average of 64 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 208 m; within 80 km, large variations in elevation — a maximum elevation change of 1,043 m.

The land around Iki is covered by trees (72%) within 3 km, water (83%) within 16 km, and water (77%) within 80 km.

3 km
152 m
16 km
208 m
80 km
1,043 m
treesgrasslandcroplandartificial surfaceswater
December weather nearby: Karatsu 44 km · Hirado 49 km · Matsuura 49 km · Itoshima 51 km · Maebaru-chūō 51 km · Imarichō-kō 58 km · Tsushima 62 km · Shingū 66 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 Iki (33.7829°, 129.7209°, elevation 45 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).