Aioi weather in January

In January, Aioi sees average daytime highs of 9°C and overnight lows near 5°C, with 50 mm of precipitation across 7.1 wet days and about 9.9 hours of daylight. It is the 12th-warmest and 12th-wettest month of the year here.

Day-to-day highs hold fairly steady near 9°C through the month. The sky is clear or mostly clear about 29% of the time in January, and the air most often feels dry.

Daylight stretches from about 9 h 42 min at the start of January to 10 h 12 min by month's end. Set against the rest of the year, January is Aioi's 5th-clearest and 1st-windiest month. For the whole year in context, see Aioi's year-round climate.

Daytime high
12th warmest
Overnight low
2nd coldest
Precipitation
50 mm
7.1 wet days
Daylight
9 h 54 min
7:14 AM – 5:09 PM
Cloud cover
57%
5th clearest
Wind
19 km/h
1st windiest
Solar energy
2.72 kWh/m²
Travel score
1.9
out of 10

Aioi is city in Hyōgo Prefecture, Japan.

Density
313/km²
people per km²
Founded
1942

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

Temperature in January

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 9°C through the month.

A typical January day in Aioi reaches about 9°C in the afternoon and slips back to 5°C overnight — a 4°C spread between the day's warmth and the night's chill. On most days the high lands between 6°C and 12°C. Set against its neighbours, January runs about 2°C cooler than December and on par with February.

10°15°151015202531
Avg high (°C)Avg low (°C)
1106
2105
395
495
595
695
795
895
995
1095
1195
1295
1395
1495
1595
1695
1795
1895
1995
2095
2194
2294
2394
2484
2584
2684
2784
2884
2984
3084
3184

How January really feels in Aioi

Once humidity and wind are folded in, January 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

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

Aioi weather by month

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

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan / 507.10.49.91.9
Feb / 637.70.610.72.0
Mar12° / 1129.9011.73.2
Apr16° / 11°13110.3012.84.9
May19° / 16°14610.2013.86.1
Jun23° / 20°18512.4014.36.0
Jul26° / 24°19312.8014.16.1
Aug28° / 25°11210.4013.36.1
Sep26° / 22°19512.3012.26.4
Oct21° / 17°1448.9011.16.8
Nov16° / 12°747010.25.5
Dec11° / 616.909.73.1

Cloud cover in January

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 29% of the time in January.

Beyond those clear spells, partly cloudy skies cover about 27% of January, with mostly cloudy or overcast conditions the remaining 43%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
16535
26535
36535
46436
56436
66337
76238
86139
96139
106040
115941
125842
135743
145644
155545
165446
175446
185248
195248
205149
215149
225149
235149
245149
255149
265149
275248
285347
295347
305347
315545

Chance of precipitation in January

Any precipitationSnow

Aioi gets around 50 mm of rain and snow over 7.1 wet days in January, the driest month. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable precipitation averages around 24% and peaks near 27% on the wettest days, and about 0 day brings snow. The odds climb toward the end of the month.

0%10%20%30%40%151015202531
Rain chance (%)Snow chance (%)
1200
2200
3200
4190
5190
6200
7200
8200
9210
10210
11221
12221
13231
14241
15241
16251
17252
18252
19262
20262
21262
22262
23273
24273
25273
26273
27273
28263
29263
30263
31253

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 19 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 19 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
1119light breeze
1219light breeze
1319light breeze
1419light breeze
1519light breeze
1619light breeze
1719light breeze
1819light breeze
1919light breeze
2019light breeze
2119light breeze
2219light breeze
2319light breeze
2419light breeze
2519light breeze
2619light breeze
2719light breeze
2819light breeze
2919light breeze
3019light breeze
3119light breeze

Sunrise & sunset in January

DaylightNight

Daylight runs from about 9 h 42 min at the start of January to 10 h 12 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 30 minutes over January. Sunrise moves from 7:14 AM to 7:08 AM, and sunset from 4:56 PM to 5:23 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
19.77:144:56
29.77:144:57
39.77:154:58
49.77:154:58
59.77:154:59
69.87:155:00
79.87:155:01
89.87:155:02
99.87:155:02
109.87:155:03
119.87:155:04
129.87:155:05
139.97:155:06
149.97:155:07
159.97:155:08
169.97:145:09
179.97:145:09
189.97:145:10
1910.07:145:11
2010.07:135:12
2110.07:135:13
2210.07:135:14
2310.07:125:15
2410.17:125:16
2510.17:115:17
2610.17:115:18
2710.17:105:19
2810.27:105:20
2910.27:095:21
3010.27:095:22
3110.27:085:23

Solar energy in January

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in January, about 2.72 kWh/m².

For context, solar energy here swings from a low near 2.43 kWh/m² to a high of 5.75 kWh/m² in May across the year — January's 2.72 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
162.6Moderate
172.7Moderate
182.7Moderate
192.7Moderate
202.7Moderate
212.7Moderate
222.8Moderate
232.8Moderate
242.8Moderate
252.9Moderate
262.9Moderate
272.9Moderate
282.9Moderate
293.0Moderate
303.0Moderate
313.0Moderate
Planning a trip in January

Hazard calendar for Aioi

In seasonPeak

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

Aioi 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 Aioi?

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

1.9
Sightseeing
12th-best month of the year
0.0
Beach & pool
11th-best month of the year

January is a weaker month for outdoor sightseeing in Aioi.

What to pack for Aioi in January

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

In January, Aioi sees daytime highs around 9°C and nights near 5°C. Pack a warm layer. About 7 days see rain.

a warm layer

Sea temperature near Aioi 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 22 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 7 to Nov 12 — about 5.2 months when the water holds above 20°C.

10°15°20°25°30°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan14Bracing
Feb13Bracing
Mar13Bracing
Apr15Bracing
May17Cool
Jun21Refreshing
Jul25Warm
Aug27Warm
Sep26Warm
Oct24Refreshing
Nov20Cool
Dec16Cool

UV index in Aioi in January

LowModerateHighVery highExtreme

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

Under clear skies, the midday UV index in Aioi peaks around July 13 at about 10 (extreme) — 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 highVery highModerateJul 13UV 10Dec 22UV 2
UV index (midday)Level
Jan3Moderate
Feb4Moderate
Mar5High
Apr7High
May8Very high
Jun10Very high
Jul10Extreme
Aug9Very high
Sep9Very high
Oct6High
Nov4Moderate
Dec2Moderate

Air quality in Aioi 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 Aioi is worst in April — around 23 µg/m³ PM2.5 (moderate), about 1.8× the cleanest month (October, 12 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateApr 1422 µg/m³Oct 1613 µg/m³
PM2.5 (µg/m³)Level
Jan15Moderate
Feb17Moderate
Mar21Moderate
Apr23Moderate
May20Moderate
Jun18Moderate
Jul15Moderate
Aug15Moderate
Sep13Moderate
Oct12Moderate
Nov13Moderate
Dec13Moderate
Location & terrain

Where is Aioi?

Aioi sits at 34.8°N, 134.5°E, 8 m above sea level, in Japan. The nearest listed city is Tatsuno, 8.0 km away.

Topography around Aioi

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

Within 3 km, the terrain around Aioi has significant variations in elevation — a maximum elevation change of 320 m around an average of 74 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 517 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,489 m.

The land around Aioi is covered by trees (65%) and artificial surfaces (22%) within 3 km, trees (48%) and water (30%) within 16 km, and trees (59%) and water (27%) within 80 km.

3 km
320 m
16 km
517 m
80 km
1,489 m
treesgrasslandcroplandartificial surfacesbare terrainwater
January weather nearby: Tatsuno 8.0 km · Kariya 9.0 km · Tatsunochō-tominaga 10 km · Ikaruga 11 km · Kamigōri 13 km · Himeji 21 km · Bizen 21 km · Shisō 22 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 Aioi (34.8036°, 134.4681°, elevation 8 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).