Mount Fuji in August: weather, what to wear and events

Mount Fuji weather in August

Averages for 1991–2020 at the JMA's Kawaguchiko station (860 m above sea level).

High: 28.1°C (83°F)
Low: 18.5°C (65°F)
Precipitation: 176.8 mm
Wet days: 10.1 days
Sunshine: 165 hours

Highs are 0.9°C above July and 4.3°C above September.

That is 11.3°C above Kawaguchiko's yearly average high of 16.8°C.

Of our 14 places with temperature records, Kawaguchiko is the 3rd coldest in August: 1.5°C cooler than Shirakawa-go and 0.1°C warmer than Nikko.

August is Kawaguchiko's 4th wettest month (176.8 mm).

Of our 15 places, Kawaguchiko has the 8th highest precipitation in August: 2.5 mm less than Kanazawa and 22.1 mm more than Tokyo.

Rain of 1 mm or more falls on 10.1 days, and 10 mm or more on 4.3 days.

Rain of 30 mm or more in one day falls on 1.6 days, and 50 mm or more on 0.9 days.

9.7 days reach 30°C or more.

The sun is out for 40% or more of the possible hours on 15.9 days, and 2.3 days have under 0.1 hours of sunshine.

On the summit of Mt Fuji (3,775 m), the average high is 9.5°C (49°F) and the low 3.8°C (39°F).

Average temperature: 22.5°C (72°F)
Humidity: 81%
Days of 25°C or more: 26.1 days

Early, mid and late August

Kawaguchiko in August by ten-day period: averages for 1991–2020 (JMA)
Days	High	Low	Precipitation
1–10 August	28.9°C	19.0°C	50.3 mm
11–20 August	28.3°C	18.8°C	55.5 mm
21–31 August	27.2°C	17.9°C	71.0 mm

By the last ten days of August the average high in Kawaguchiko is 1.7°C lower than in the first ten.

By ten-day totals, 21–31 August is the wettest (71.0 mm) and 1–10 August the driest (50.3 mm).

What to wear at Mount Fuji in August

Warm: highs around 28.1°C

This is for Kawaguchiko (860 m above sea level).

Short sleeves or thin long sleeves, with a light layer for air-conditioning and evenings.
Humidity averages 81%: quick-dry fabrics are more comfortable.
An umbrella: rain falls on 10.1 days.

Climbing Mt Fuji: the summit averages a high of 9.5°C (49°F) and a low of 3.8°C (39°F) in August. Pack warm, windproof layers.

Pack

Umbrella
Quick-dry clothes
A light layer for air-conditioning

Our clothing rules

Rainy season and typhoons

In an average August, 0.8 typhoons come within 300 km of the Kanto-Koshin region; across Japan, 3.3 come within 300 km and 0.9 make landfall (JMA, 1991–2020).

August records at Mount Fuji

The extremes the JMA has measured in August at its Kawaguchiko station.

Hottest August day: 35.0°C (95°F) on 9 August 2013 (records since 1933)
Coldest August night: 9.3°C (49°F) on 20 August 1956 (records since 1933)
Wettest August day: 463.5 mm on 16 August 1983 (records since 1933)

Holidays and crowds in August

National holidays in August 2027:

Wed 11 August — Mountain Day

In August 2025, hotels and inns across Yamanashi Prefecture were 60.5% full on average (the busiest month of the year). Foreign guests spent 226,190 nights there that month (Japan Tourism Agency). That compares with 48.8% in July and 46.5% in September.

What's on at Mount Fuji in August

Events at Mount Fuji in August: dates from each organizer's official page
Event	When	Where and what
Mt Fuji climbing season, Yoshida Trail (Yamanashi side)富士山吉田ルート登山シーズン	1 July to 10 September; the start may be delayed by weather or remaining snow	Yoshida Trail, Mt Fuji (Yamanashi side); gear is checked at the 5th station. The climbing season of the Yoshida Trail. Access is regulated: a trail toll of 4,000 yen per person per climb, a gate closed from 14:00 to 3:00 (except for mountain-hut guests), and a limit of 4,000 climbers a day (hut guests excluded). Climbers without the required gear (warm clothing, rain gear in separate top and bottom pieces, and climbing footwear) cannot use the trail. Advance reservation (also possible on the day) is recommended. The standard time to the summit is about 6 hours up and 4 hours down plus 1 hour of rest. The prefecture warns that overnight climbing without staying in a hut (bullet climbing) is dangerous. Official page
Kawaguchiko Lake Festival (Kojosai) fireworks河口湖湖上祭	5 August every year	Lakeside of Lake Kawaguchi: Funatsu-hama and Hirahama car park and Oike Park. A fireworks festival with musical fireworks, large shells and starmines over the lake, with stalls along the lakeshore from Oike Park to the Komagari Tunnel. The festival has been held more than 100 times. From the 2024 edition shown on the official page: traffic restrictions were put in place on the lakeside roads on the day, the prefectural Funatsu-hama and Hirahama car parks could not be used, extra Fuji Kyuko line trains ran, and the fireworks ran from 19:45 to 20:40. The 2026 details were not available on the official pages checked. Official page
Yoshida Fire Festival (Yoshida no Himatsuri) and Susuki Festival吉田の火祭り・すすき祭り	26 and 27 August every year	Kitaguchi Hongu Fuji Sengen Shrine and Suwa Shrine, Kamiyoshida, Fujiyoshida; the Otabisho is at the Kamiyoshida Community Center. The festival of Kitaguchi Hongu Fuji Sengen Shrine and Suwa Shrine. On 26 August two portable shrines tour the district; when they are enshrined at the Otabisho in the evening, more than 100 large torches about 3 m high are lit along a route of about 2 km. On 27 August the portable shrines tour the district again, and the festival peaks with the susuki-grass offering procession in the shrine grounds. Times on the official page: 26 August, rituals at 14:30, portable shrine procession from 17:00, arrival at the Otabisho at 18:30 when the torches are lit, torches taken down from 22:00; 27 August, ritual at the Otabisho at 13:15, portable shrines set out at 14:00, Kanadori-i festival at 15:30, Mikuraishi festival at 18:00, ritual at the shrine at 19:00. Official page
Rainbow Flower Festival (Niji no Hana Matsuri)虹の花まつり	Late August to mid-October (29 August to 12 October in 2026, listed as planned)	Fuji Motosuko Resort, Motosu, Fujikawaguchiko Town (altitude about 1,000 m). A flower event with about 80,000 plants of 10 varieties, including zinnias in yellow, red, pink and orange and Rudbeckia 'Prairie Sun', on the grounds of Fuji Motosuko Resort at the foot of Mt Fuji. 2026 is the fifth year. The period varies with the season. A dog run for small and medium dogs up to 50 cm tall is on site; dogs must be on a lead in the grounds and are not allowed indoors. Official page

Mount Fuji before and after August

Kawaguchiko: July, August and September (JMA, 1991–2020)
Month	High	Low	Precipitation	Wet days
July	27.2°C (−0.9°C)	18.0°C (−0.5°C)	178.4 mm (+1.6 mm)	11.7 days (+1.6 days)
August	28.1°C	18.5°C	176.8 mm	10.1 days
September	23.8°C (−4.3°C)	14.8°C (−3.7°C)	264.7 mm (+87.9 mm)	11.1 days (+1.0 days)

Other places in August

August: Kawaguchiko against five other places (JMA, 1991–2020)
Place	High	Against Kawaguchiko	Wet days	Against Kawaguchiko
Tokyo	31.3°C	+3.2°C	7.9 days	−2.2 days
Kyoto	33.7°C	+5.6°C	8.3 days	−1.8 days
Osaka	33.7°C	+5.6°C	7.2 days	−2.9 days
Sapporo	26.4°C	−1.7°C	9.5 days	−0.6 days
OkinawaNaha	31.8°C	+3.7°C	12.3 days	+2.2 days

All 15 places in August

Frequently asked questions

What is the weather like at Mount Fuji in August?

The average high is 28.1°C (83°F) and the average low 18.5°C (65°F). 176.8 mm of rain falls on about 10.1 days (JMA, 1991–2020).

What should I wear at Mount Fuji in August?

Short sleeves or thin long sleeves, with a light layer for air-conditioning and evenings. Humidity averages 81%: quick-dry fabrics are more comfortable. An umbrella: rain falls on 10.1 days.

Is Mount Fuji busy in August?

In August 2025, hotels and inns across Yamanashi Prefecture were 60.5% full on average (the busiest month of the year). Foreign guests spent 226,190 nights there that month (Japan Tourism Agency).

What are the record temperatures for August at Mount Fuji?

The highest temperature the JMA has recorded in Kawaguchiko in August is 35.0°C (95°F), on 9 August 2013. The lowest is 9.3°C (49°F), on 20 August 1956.

What events are on at Mount Fuji in August?

Mt Fuji climbing season, Yoshida Trail (Yamanashi side): 1 July to 10 September; the start may be delayed by weather or remaining snow. Kawaguchiko Lake Festival (Kojosai) fireworks: 5 August every year. Yoshida Fire Festival (Yoshida no Himatsuri) and Susuki Festival: 26 and 27 August every year. Rainbow Flower Festival (Niji no Hana Matsuri): Late August to mid-October (29 August to 12 October in 2026, listed as planned).

Related items

Sources for this page

Japan Meteorological Agency (JMA) Normals for 1991–2020: Kawaguchiko (河口湖), month by month (平年値年・月ごとの値)checked October 2, 2026
Japan Meteorological Agency (JMA) Normals for 1991–2020: Kawaguchiko (河口湖), rain days, temperature days and snow (詳細)checked October 2, 2026
Japan Meteorological Agency (JMA) Normals for 1991–2020: Mt Fuji summit (富士山), month by month (平年値年・月ごとの値)checked October 2, 2026
Japan Meteorological Agency (JMA) Ten-day normals for 1991–2020: Kawaguchiko (河口湖) (平年値旬ごとの値)checked October 2, 2026
Japan Meteorological Agency (JMA) Records for August: Kawaguchiko (河口湖) (観測史上1〜10位の値)checked October 2, 2026
Japan Meteorological Agency (JMA) Typhoon averages, 1991–2020 (台風の平年値)checked October 2, 2026
Cabinet Office National holidays (国民の祝日について)checked October 2, 2026
Japan Tourism Agency Overnight Travel Statistics Survey, 2025 final figures (宿泊旅行統計調査 2025年年の確定値)checked October 2, 2026
Yamanashi Prefecture, Mt Fuji Tourism Promotion Group Mt Fuji climbing season, Yoshida Trail (Yamanashi side) (富士山吉田ルート登山シーズン)checked October 2, 2026
Yamanashi Tourism Organization (Yamanashi Prefecture official tourism site) Kawaguchiko Lake Festival (Kojosai) fireworks (河口湖湖上祭)checked October 2, 2026
Fujiyoshida Tourism Promotion Service (Fujiyoshida tourism guide); contact: Kitaguchi Hongu Fuji Sengen Shrine Yoshida Fire Festival (Yoshida no Himatsuri) and Susuki Festival (吉田の火祭り・すすき祭り)checked October 2, 2026
Fuji Motosuko Resort Rainbow Flower Festival (Niji no Hana Matsuri) (虹の花まつり)checked October 2, 2026

Mount Fuji in August: weather, what to wear and what's on