Sayama weather in January

In January, Sayama sees average daytime highs of 7°C and overnight lows near -0°C, with 64 mm of precipitation across 7.9 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 7°C through the month. The sky is clear or mostly clear about 22% 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 Sayama's 4th-clearest and 4th-windiest month. For the whole year in context, see Sayama's year-round climate.

Daytime high
12th warmest
Overnight low
-0°
1st coldest
Precipitation
64 mm
7.9 wet days
Daylight
9 h 54 min
7:09 AM – 5:03 PM
Cloud cover
60%
4th clearest
Wind
9 km/h
4th windiest
Solar energy
2.53 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 Sayama reaches about 7°C in the afternoon and slips back to -0°C overnight — a 8°C spread between the day's warmth and the night's chill. On most days the high lands between 4°C and 11°C. Set against its neighbours, January runs about 3°C cooler than December and about 1°C cooler than February.

-5°10°15°151015202531
Avg high (°C)Avg low (°C)
181
281
381
480
580
680
780
880
980
1080
1180
1270
1370
1470
1570
1670
1770
1870
1970
2070
2170
2270
2370
2470
2570
2670
2770
2870
2970
3070
3170

How January really feels in Sayama

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.

Sayama 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 / -0°647.92.39.91.1
Feb / 708.92.310.71.5
Mar12° / 12212.40.611.73.1
Apr18° / 13311.7012.95.4
May23° / 13°15311.6013.86.4
Jun26° / 18°20514.6014.35.6
Jul30° / 22°23917.6014.14.2
Aug31° / 23°14013.5013.34.1
Sep27° / 19°18712.9012.25.8
Oct21° / 13°1619.9011.16.6
Nov16° / 847.6010.25.1
Dec10° / 657.719.72.4

Cloud cover in January

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 22% of the time in January.

Beyond those clear spells, partly cloudy skies cover about 31% of January, with mostly cloudy or overcast conditions the remaining 46%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
16238
26238
36139
46139
56040
66040
75941
85941
95842
105743
115644
125545
135446
145446
155347
165248
175149
184951
194951
204951
214852
224852
234951
244951
254951
264951
274951
285050
295050
305149
315149

Chance of precipitation in January

Any precipitationSnow

Sayama gets around 64 mm of rain and snow over 7.9 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 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 (%)
1248
2248
3248
4248
5248
6248
7247
8247
9247
10257
11257
12268
13268
14278
15278
16278
17278
18288
19288
20288
21288
22288
23288
24288
25288
26289
27279
28279
29279
30279
31279

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 9 km/h in January.

Across January, daily wind ranges from about 9 km/h on the calmest days to 9 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (km/h)Feels
19calm
29calm
39calm
49calm
59calm
69calm
79calm
89calm
99calm
109calm
119calm
129calm
139calm
149calm
159calm
169calm
179calm
189calm
199calm
209calm
219calm
229calm
239calm
249calm
259calm
269calm
279calm
289calm
299calm
309calm
319calm

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 7:09 AM to 7:03 AM, and sunset from 4:51 PM to 5:18 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
19.77:094:51
29.77:104:52
39.77:104:52
49.77:104:53
59.77:104:54
69.77:104:55
79.87:104:55
89.87:104:56
99.87:104:57
109.87:104:58
119.87:104:59
129.87:105:00
139.87:105:01
149.97:105:01
159.97:105:02
169.97:095:03
179.97:095:04
189.97:095:05
1910.07:095:06
2010.07:085:07
2110.07:085:08
2210.07:085:09
2310.07:075:10
2410.17:075:11
2510.17:065:12
2610.17:065:13
2710.17:055:14
2810.27:055:15
2910.27:045:16
3010.27:045:17
3110.27:035:18

Solar energy in January

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in January, about 2.53 kWh/m².

For context, solar energy here swings from a low near 2.25 kWh/m² to a high of 5.41 kWh/m² in May across the year — January's 2.53 kWh/m² sits near the bottom.

0123151015202531
Solar energy (kWh/m²)Level
12.4Moderate
22.4Moderate
32.4Moderate
42.4Moderate
52.4Moderate
62.4Moderate
72.4Moderate
82.4Moderate
92.4Moderate
102.4Moderate
112.4Moderate
122.4Moderate
132.4Moderate
142.4Moderate
152.5Moderate
162.5Moderate
172.5Moderate
182.5Moderate
192.5Moderate
202.5Moderate
212.6Moderate
222.6Moderate
232.6Moderate
242.6Moderate
252.7Moderate
262.7Moderate
272.7Moderate
282.7Moderate
292.8Moderate
302.8Moderate
312.8Moderate
Planning a trip in January

Hazard calendar for Sayama

In seasonPeak

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

Sayama 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 Sayama?

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

1.1
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 Sayama.

What to pack for Sayama in January

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

In January, Sayama sees daytime highs around 7°C and nights near -0°C. Pack a warm layer. Worth having: a heavy coat. About 8 days see rain.

a warm layera heavy coat

Sea temperature near Sayama 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 44 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 6 to Nov 11 — 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
Apr15Cool
May18Cool
Jun21Refreshing
Jul25Warm
Aug27Warm
Sep26Warm
Oct23Refreshing
Nov20Cool
Dec17Cool

UV index in Sayama 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 Sayama peaks around July 10 at about 10 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 23 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 10UV 10Dec 23UV 3
UV index (midday)Level
Jan3Moderate
Feb4Moderate
Mar5High
Apr7High
May8Very high
Jun10Very high
Jul10Very high
Aug8Very high
Sep9Very high
Oct6High
Nov4Moderate
Dec3Moderate

Air quality in Sayama 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 Sayama is worst in April — around 24 µg/m³ PM2.5 (moderate), about 2.0× the cleanest month (October, 12 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateApr 1723 µg/m³Oct 1812 µg/m³
PM2.5 (µg/m³)Level
Jan14Moderate
Feb17Moderate
Mar22Moderate
Apr24Moderate
May22Moderate
Jun19Moderate
Jul17Moderate
Aug17Moderate
Sep14Moderate
Oct12Good
Nov13Moderate
Dec12Moderate
Location & terrain

Where is Sayama?

Sayama sits at 34.9°N, 135.8°E, 14 m above sea level, in Japan. The nearest listed city is Yawata, 4.0 km away.

Topography around Sayama

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

Within 3 km, the terrain around Sayama has only modest variations in elevation — a maximum elevation change of 54 m around an average of 16 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 683 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,882 m.

The land around Sayama is covered by artificial surfaces (57%) and cropland (29%) within 3 km, trees (49%) and artificial surfaces (38%) within 16 km, and trees (65%) within 80 km.

3 km
54 m
16 km
683 m
80 km
1,882 m
treesgrasslandcroplandartificial surfacesbare terrainwater
January weather nearby: Yawata 4.0 km · Uji 5.0 km · Tanabe 6.0 km · Jōyō 6.0 km · Oyamazaki 6.0 km · Kōtari 7.0 km · Minase 8.0 km · Kyōtanabe 8.0 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 Sayama (34.8753°, 135.7502°, elevation 14 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).