Iwaki in Winter
In winter (December, January and February), Iwaki sees average daytime highs around 8°C and overnight lows near 4°C, with 212 mm of precipitation over about 25 wet days across the season. It is the coldest season of the year and the driest season of the year.
Over the season highs ease from about 12°C in early December to 8°C by late February. The sky is clear or mostly clear about 50% of the time across winter, and the air most often feels dry.
Winter is Iwaki's weakest season of the year to visit on our travel score. For the whole year in context, see Iwaki's year-round climate.
- Avg daytime high
- 8°C
- coldest season of the year
- Avg overnight low
- 4°C
- Precipitation
- 212 mm
- 25 wet days
- Avg wind
- 19 km/h
- Travel score
- 1.5
- weakest season of the year
- Months
- Dec · Jan · Feb
Temperature in Iwaki in Winter
Over the season highs ease from about 12°C in early December to 8°C by late February.
A typical winter day in Iwaki reaches about 8°C and drops to 4°C overnight. The warmest of the three months is December, the coolest February.
How winter really feels in Iwaki
Once humidity and wind are folded in, winter brings about 0 days that feel above 32°C and 61 that feel at or below 0°C.
The story in winter is cold — wind chill drags the overnight "feels like" below the raw low.
Iwaki weather by month
How the three winter months (December, January and February) compare with the rest of the year — the season's months are highlighted.
| Month | High / Low (°C) | Rainfall (mm) | Wet days | Snow days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|---|
| Jan | 7° / 3° | 71 | 8 | 1.5 | 9.7 | 1.1 |
| Feb | 7° / 3° | 68 | 8 | 1.9 | 10.6 | 1.1 |
| Mar | 10° / 5° | 125 | 12.1 | 1 | 11.7 | 2.1 |
| Apr | 13° / 9° | 134 | 11.9 | 0.2 | 12.9 | 3.6 |
| May | 17° / 13° | 145 | 12 | 0 | 14 | 5.1 |
| Jun | 20° / 17° | 147 | 13.7 | 0 | 14.5 | 5.4 |
| Jul | 23° / 20° | 175 | 14.5 | 0 | 14.3 | 5.9 |
| Aug | 25° / 22° | 126 | 11.8 | 0 | 13.4 | 6.5 |
| Sep | 23° / 20° | 192 | 14.1 | 0 | 12.3 | 5.9 |
| Oct | 19° / 15° | 223 | 13.4 | 0 | 11 | 5.6 |
| Nov | 14° / 10° | 111 | 9.8 | 0 | 10 | 4.4 |
| Dec | 10° / 6° | 73 | 8.6 | 0.2 | 9.5 | 2.3 |
Cloud cover in Winter
The sky is clear or mostly clear about 50% of the time across winter.
Chance of precipitation in Winter
Iwaki gets around 212 mm of rain and snow over 25 wet days across winter. The line is the day-by-day chance of measurable precipitation.
Humidity in Winter
Most of winter feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Winter
Winds average 19 km/h across winter.
Sunrise & sunset in Winter
Daylight runs from about 9 h 36 min in early December to 11 h 06 min by late February. The lit band spans sunrise to sunset each day.
Solar energy in Winter
Average shortwave solar energy reaching the ground each day across winter, about 2.8 kWh/m².
Hazard calendar for Iwaki
In winter, Iwaki overlaps 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.
Is winter a good time to visit Iwaki?
Our two travel scores rate winter for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal), averaged across the three months.
winter is a weaker month for outdoor sightseeing in Iwaki.
What to pack for Iwaki in Winter
From winter's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In winter, Iwaki sees daytime highs around 8°C and nights near 4°C. Pack a warm layer. Worth having: a heavy coat and rain gear. About 25 days see rain.
Sea temperature near Iwaki in Winter
The nearest coast averages about 14°C across winter — 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.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sea temperature (°C) | 14 | 12 | 12 | 14 | 16 | 19 | 21 | 24 | 23 | 20 | 18 | 16 |
| Comfort | Bracing | Bracing | Bracing | Bracing | Cool | Cool | Refreshing | Refreshing | Refreshing | Refreshing | Cool | Cool |
| Sea temperature (°C) | Comfort | |
|---|---|---|
| Jan | 14 | Bracing |
| Feb | 12 | Bracing |
| Mar | 12 | Bracing |
| Apr | 14 | Bracing |
| May | 16 | Cool |
| Jun | 19 | Cool |
| Jul | 21 | Refreshing |
| Aug | 24 | Refreshing |
| Sep | 23 | Refreshing |
| Oct | 20 | Refreshing |
| Nov | 18 | Cool |
| Dec | 16 | Cool |
UV index in Iwaki in Winter
Clear-sky midday UV across winter averages 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.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 2 | 3 | 4 | 6 | 8 | 9 | 9 | 9 | 8 | 5 | 3 | 2 |
| Level | Low | Moderate | Moderate | High | Very high | Very high | Very high | Very high | Very high | High | Moderate | Low |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 2 | Low |
| Feb | 3 | Moderate |
| Mar | 4 | Moderate |
| Apr | 6 | High |
| May | 8 | Very high |
| Jun | 9 | Very high |
| Jul | 9 | Very high |
| Aug | 9 | Very high |
| Sep | 8 | Very high |
| Oct | 5 | High |
| Nov | 3 | Moderate |
| Dec | 2 | Low |
Air quality in Iwaki in Winter
Average fine-particle pollution (PM2.5) through the year — so you can see where winter 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).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 (µg/m³) | 8 | 11 | 17 | 19 | 19 | 14 | 12 | 11 | 10 | 10 | 9 | 7 |
| Level | Good | Good | Moderate | Moderate | Moderate | Moderate | Moderate | Good | Good | Good | Good | Good |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 8 | Good |
| Feb | 11 | Good |
| Mar | 17 | Moderate |
| Apr | 19 | Moderate |
| May | 19 | Moderate |
| Jun | 14 | Moderate |
| Jul | 12 | Moderate |
| Aug | 11 | Good |
| Sep | 10 | Good |
| Oct | 10 | Good |
| Nov | 9 | Good |
| Dec | 7 | Good |
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.
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
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.