Iwaki weather in January

In January, Iwaki sees average daytime highs of 7°C and overnight lows near 3°C, with 71 mm of precipitation across 8 wet days and about 9.7 hours of daylight. It is the 12th-warmest and 11th-wettest month of the year here.

Day-to-day highs hold fairly steady near 7°C through the month. The sky is clear or mostly clear about 54% of the time in January, and the air most often feels dry.

Daylight stretches from about 9 h 30 min at the start of January to 10 h 06 min by month's end. Set against the rest of the year, January is Iwaki's 2nd-clearest and 1st-windiest month. For the whole year in context, see Iwaki's year-round climate.

Daytime high
12th warmest
Overnight low
2nd coldest
Precipitation
71 mm
8 wet days
Daylight
9 h 42 min
6:54 AM – 4:37 PM
Cloud cover
43%
2nd clearest
Wind
20 km/h
1st windiest
Solar energy
2.74 kWh/m²
Travel score
1.1
out of 10

Temperature in January

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 7°C through the month.

A typical January day in Iwaki reaches about 7°C in the afternoon and slips back to 3°C overnight — a 4°C spread between the day's warmth and the night's chill. On most days the high lands between 4°C and 10°C. Set against its neighbours, January runs about 3°C cooler than December and on par with February.

-5°10°15°151015202531
Avg high (°C)Avg low (°C)
184
284
384
484
584
683
773
873
973
1073
1173
1273
1373
1473
1573
1673
1773
1873
1973
2073
2173
2273
2373
2473
2573
2673
2772
2872
2972
3072
3172

How January really feels in Iwaki

Once humidity and wind are folded in, January 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 January is cold — wind chill drags the overnight "feels like" below the raw low.

Iwaki weather by month

How January compares with the rest of the year at a glance. January is the 12th-warmest and 11th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan / 7181.59.71.1
Feb / 6881.910.61.1
Mar10° / 12512.1111.72.1
Apr13° / 13411.90.212.93.6
May17° / 13°145120145.1
Jun20° / 17°14713.7014.55.4
Jul23° / 20°17514.5014.35.9
Aug25° / 22°12611.8013.46.5
Sep23° / 20°19214.1012.35.9
Oct19° / 15°22313.40115.6
Nov14° / 10°1119.80104.4
Dec10° / 738.60.29.52.3

Cloud cover in January

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 54% of the time in January.

Beyond those clear spells, partly cloudy skies cover about 16% of January, with mostly cloudy or overcast conditions the remaining 30%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
17624
27624
37624
47525
57525
67525
77525
87426
97426
107228
117228
127129
137030
146931
156931
166832
176733
186634
196634
206634
216634
226634
236634
246733
256733
266733
276832
286733
296832
306832
316931

Chance of precipitation in January

Any precipitationSnow

Iwaki gets around 71 mm of rain and snow over 8 wet days in January. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable precipitation averages around 26% and peaks near 28% on the wettest days, and about 2 days bring snow.

0%10%20%30%40%151015202531
Rain chance (%)Snow chance (%)
1222
2222
3222
4232
5232
6242
7242
8243
9253
10253
11263
12264
13274
14275
15285
16285
17286
18286
19286
20286
21286
22287
23287
24287
25287
26287
27287
28277
29277
30287
31287

Humidity in January

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, January 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 January

Winds average 20 km/h in January, the windiest month of the year.

Across January, daily wind ranges from about 19 km/h on the calmest days to 20 km/h at its breeziest. It stays fairly steady from day to day.

0510152025151015202531
Wind speed (km/h)Feels
119light breeze
219light breeze
319light breeze
419light breeze
519light breeze
619light breeze
719light breeze
819light breeze
919light breeze
1019light breeze
1120light breeze
1220light breeze
1320light breeze
1420light breeze
1520light breeze
1620light breeze
1720light breeze
1820light breeze
1920light breeze
2020light breeze
2120light breeze
2220light breeze
2320light breeze
2420light breeze
2520light breeze
2620light breeze
2720light breeze
2820light breeze
2920light breeze
3019light breeze
3119light breeze

Sunrise & sunset in January

DaylightNight

Daylight runs from about 9 h 30 min at the start of January to 10 h 06 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 36 minutes over January. Sunrise moves from 6:55 AM to 6:47 AM, and sunset from 4:25 PM to 4:53 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
19.56:554:25
29.56:554:25
39.56:554:26
49.56:554:27
59.56:554:28
69.66:554:28
79.66:554:29
89.66:554:30
99.66:554:31
109.66:554:32
119.66:554:33
129.66:554:34
139.76:554:34
149.76:554:35
159.76:544:36
169.76:544:37
179.76:544:38
189.86:544:39
199.86:534:40
209.86:534:41
219.86:534:42
229.96:524:43
239.96:524:44
249.96:514:45
259.96:514:46
2610.06:504:47
2710.06:504:48
2810.06:494:49
2910.06:484:51
3010.16:484:52
3110.16:474:53

Solar energy in January

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in January, about 2.74 kWh/m².

For context, solar energy here swings from a low near 2.32 kWh/m² to a high of 5.47 kWh/m² in May across the year — January's 2.74 kWh/m² sits near the bottom.

01234151015202531
Solar energy (kWh/m²)Level
12.6Moderate
22.6Moderate
32.6Moderate
42.6Moderate
52.6Moderate
62.6Moderate
72.6Moderate
82.6Moderate
92.6Moderate
102.6Moderate
112.6Moderate
122.6Moderate
132.6Moderate
142.6Moderate
152.6Moderate
162.7Moderate
172.7Moderate
182.7Moderate
192.7Moderate
202.7Moderate
212.8Moderate
222.8Moderate
232.8Moderate
242.8Moderate
252.9Moderate
262.9Moderate
272.9Moderate
283.0Moderate
293.0Moderate
303.0Moderate
313.0Moderate
Planning a trip in January

Hazard calendar for Iwaki

In seasonPeak

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

Iwaki 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 January a good time to visit Iwaki?

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

1.1
Sightseeing
11th-best month of the year
0.0
Beach & pool
9th-best month of the year

January is a weaker month for outdoor sightseeing in Iwaki.

What to pack for Iwaki in January

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

In January, Iwaki sees daytime highs around 7°C and nights near 3°C. Pack a warm layer. Worth having: a heavy coat and rain gear. About 8 days see rain.

a warm layera heavy coatrain gear

Sea temperature near Iwaki in January

The nearest coast averages about 14°C in January — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 19 km away) is warmest in August at about 24°C and coldest in March near 12°C.

It's comfortable for a long swim from Jul 1 to Oct 22 — about 3.7 months when the water holds above 20°C.

10°15°20°25°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmcomfortable to swim
Sea temperature (°C)Comfort
Jan14Bracing
Feb12Bracing
Mar12Bracing
Apr14Bracing
May16Cool
Jun19Cool
Jul21Refreshing
Aug24Refreshing
Sep23Refreshing
Oct20Refreshing
Nov18Cool
Dec16Cool

UV index in Iwaki in January

LowModerateHighVery highExtreme

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

Under clear skies, the midday UV index in Iwaki peaks around July 18 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near January 1 at about 2 (low).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highModerateJul 18UV 9Jan 1UV 2
UV index (midday)Level
Jan2Low
Feb3Moderate
Mar4Moderate
Apr6High
May8Very high
Jun9Very high
Jul9Very high
Aug9Very high
Sep8Very high
Oct5High
Nov3Moderate
Dec2Low

Air quality in Iwaki in January

GoodModeratePoorUnhealthyVery unhealthy

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

Air quality in Iwaki is worst in April — around 19 µg/m³ PM2.5 (moderate), about 2.8× the cleanest month (December, 7 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodApr 2219 µg/m³Dec 177 µg/m³
PM2.5 (µg/m³)Level
Jan8Good
Feb11Good
Mar17Moderate
Apr19Moderate
May19Moderate
Jun14Moderate
Jul12Moderate
Aug11Good
Sep10Good
Oct10Good
Nov9Good
Dec7Good
Location & terrain

Where is Iwaki?

Iwaki sits at 37.0°N, 140.9°E, 9 m above sea level, in Japan. The nearest listed city is Kitaibaraki, 32 km away.

Topography around Iwaki

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

Within 3 km, the terrain around Iwaki has only modest variations in elevation — a maximum elevation change of 129 m around an average of 35 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 776 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,678 m.

The land around Iwaki is covered by artificial surfaces (46%) and trees (41%) within 3 km, trees (57%) and water (22%) within 16 km, and trees (55%) and water (32%) within 80 km.

3 km
129 m
16 km
776 m
80 km
1,678 m
treesgrasslandcroplandartificial surfacesbare terrainwater
January weather nearby: Kitaibaraki 32 km · Takahagi 40 km · Ishikawa 40 km · Tamura 49 km · Namie 49 km · Sukagawa 51 km · Funehikimachi-funehiki 52 km · Yabuki 53 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 Iwaki (37.05°, 140.8833°, elevation 9 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).