Iwaki weather in August

In August, Iwaki sees average daytime highs of 25°C and overnight lows near 22°C, with 126 mm of rain across 11.8 wet days and about 13.4 hours of daylight. It is the 1st-warmest and 7th-wettest month of the year here.

Day-to-day highs hold fairly steady near 25°C through the month. The sky is clear or mostly clear about 23% of the time in August, and the air most often feels oppressive.

Daylight stretches from about 13 h 54 min at the start of August to 12 h 54 min by month's end. Set against the rest of the year, August is Iwaki's 8th-clearest and 11th-windiest month. For the whole year in context, see Iwaki's year-round climate.

Daytime high
25°
1st warmest
Overnight low
22°
12th coldest
Rainfall
126 mm
11.8 wet days
Daylight
13 h 24 min
4:58 AM – 6:23 PM
Cloud cover
65%
8th clearest
Wind
12 km/h
11th windiest
Solar energy
4.88 kWh/m²
Travel score
6.5
out of 10

Temperature in August

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 25°C through the month.

A typical August day in Iwaki reaches about 25°C in the afternoon and slips back to 22°C overnight — a 3°C spread between the day's warmth and the night's chill. On most days the high lands between 22°C and 27°C. Set against its neighbours, August runs about 2°C warmer than July and about 2°C warmer than September.

15°20°25°30°151015202531
Avg high (°C)Avg low (°C)
12422
22422
32522
42522
52522
62522
72522
82522
92522
102522
112522
122522
132522
142522
152522
162522
172522
182522
192522
202522
212522
222522
232522
242522
252522
262522
272522
282522
292422
302422
312422

How August really feels in Iwaki

Once humidity and wind are folded in, August 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

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

Iwaki weather by month

How August compares with the rest of the year at a glance. August is the 1st-warmest and 7th-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 August

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 23% of the time in August.

Beyond those clear spells, partly cloudy skies cover about 16% of August, with mostly cloudy or overcast conditions the remaining 61%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
13961
23961
34060
44159
54060
64060
74060
84060
94060
104060
113961
124060
134060
143961
153961
164060
174060
183961
193961
203961
214060
223961
233961
243961
253961
263961
273961
283961
293961
303862
313862

Chance of precipitation in August

Any precipitation

Iwaki gets around 126 mm of rain over 11.8 wet days in August. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 39% and peaks near 46% on the wettest days. The odds climb toward the end of the month.

0%20%40%60%151015202531
Rain chance (%)
133
232
332
432
532
632
732
833
934
1035
1136
1237
1338
1438
1539
1639
1740
1840
1940
2041
2141
2242
2342
2443
2543
2644
2744
2844
2945
3046
3146

Humidity in August

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, August lands in the oppressive band about 58% of days. Sticky, muggy-or-worse air turns up on roughly 90% of them.

0%25%50%75%100%151015202531
Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
11725625
21723636
31723636
41722646
51721647
61721647
71720657
81720648
91720648
101820638
111821628
121821628
131822618
141823608
152823607
162824597
172825587
182826577
192826586
202827576
212828566
223829555
233830545
242831545
252932534
262932534
2721033523
2821033523
2921134503
3021134503
3121234493

Wind in August

Winds average 12 km/h in August.

Across August, daily wind ranges from about 12 km/h on the calmest days to 13 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (km/h)Feels
112light breeze
212light breeze
312light breeze
412light breeze
512light breeze
612light breeze
712light breeze
812light breeze
912light breeze
1012light breeze
1112light breeze
1212light breeze
1312light breeze
1412light breeze
1512light breeze
1612light breeze
1712light breeze
1812light breeze
1912light breeze
2012light breeze
2112light breeze
2212light breeze
2312light breeze
2413light breeze
2513light breeze
2613light breeze
2713light breeze
2813light breeze
2913light breeze
3013light breeze
3113light breeze

Sunrise & sunset in August

DaylightNight

Daylight runs from about 13 h 54 min at the start of August to 12 h 54 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 60 minutes over August. Sunrise moves from 4:45 AM to 5:10 AM, and sunset from 6:40 PM to 6:03 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
113.94:456:40
213.94:466:39
313.94:476:38
413.84:476:37
513.84:486:36
613.84:496:35
713.74:506:34
813.74:516:33
913.74:526:32
1013.64:536:31
1113.64:536:30
1213.64:546:28
1313.54:556:27
1413.54:566:26
1513.54:576:25
1613.44:586:23
1713.44:586:22
1813.44:596:21
1913.35:006:20
2013.35:016:18
2113.35:026:17
2213.25:036:16
2313.25:046:14
2413.15:046:13
2513.15:056:11
2613.15:066:10
2713.05:076:09
2813.05:086:07
2912.95:096:06
3012.95:106:04
3112.95:106:03

Solar energy in August

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in August, about 4.88 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 — August's 4.88 kWh/m² falls in the middle.

0246151015202531
Solar energy (kWh/m²)Level
15.2Bright
25.2Bright
35.2Bright
45.2Bright
55.2Bright
65.2Bright
75.2Bright
85.1Bright
95.1Bright
105.1Bright
115.0Bright
125.0Bright
135.0Bright
144.9Bright
154.9Bright
164.9Bright
174.8Bright
184.8Bright
194.8Bright
204.7Bright
214.7Bright
224.7Bright
234.6Bright
244.6Bright
254.6Bright
264.5Bright
274.5Bright
284.5Bright
294.5Bright
304.4Bright
314.4Bright
Planning a trip in August

Hazard calendar for Iwaki

In seasonPeak

In August, 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 August a good time to visit Iwaki?

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

6.5
Sightseeing
1st-best month of the year
5.7
Beach & pool
1st-best month of the year

August is a reasonable time to visit Iwaki for sightseeing.

What to pack for Iwaki in August

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

In August, Iwaki sees daytime highs around 25°C and nights near 22°C. Worth packing: light clothes, rain gear and sun protection. About 12 days see rain.

light clothesrain gearsun protection

Sea temperature near Iwaki in August

The nearest coast averages about 24°C in August — 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 August

LowModerateHighVery highExtreme

Clear-sky midday UV in August peaks around 9 (very high — sun protection essential). 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 August

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where August 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
August 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).