In September 2025, with Expo 2025 Osaka packed in its final weeks, the Yomiuri Shimbun ran a photograph of visitors streaming past each other under parasols (20 September). The headline quoted a complaint: they hit you in the head. The story was about parasols becoming so common that they had turned into a hazard in the crowds. No survey shows how many of them were men; nationwide, the share of men using a parasol had risen from 8.0% to 17.8% in two years (Men’s Rize, April 2025).
The 3,000 loan parasols the Association announced, and the rest of its heat plan
On 11 July 2025 the Japan Association for the 2025 World Exposition set out its heat measures under three headings. At the East Entrance plaza it would lend out 3,000 parasols and set up rest areas. Eighteen mist fans were placed between the second and first transport terminals. Two electric buses were turned into rest areas. There were 248 vending machines on site (as of 15 June) and 79 water points, from mains-fed fountains to water servers. Eight first-aid stations were set up to treat people while symptoms were still mild. On 14 July the Association handed out salt tablets and sweets under the Grand Ring.
The official blog of 27 June adds that ten free bottle-washing machines were installed and that three mobile benches called Soraisu, built from discarded solar panels, were in service. The Association announced parasol loans, and supplied water and places to sit.
According to the Yomiuri of 20 September, around the East and West Gates and the popular pavilions people with parasols were passing each other at close quarters, some of them looking at their phones, and posts complaining about parasols catching eyes and heads had piled up on social media. The Association, the paper said, was urging safe use.
Men’s parasols in numbers
There is no survey of parasol use among expo visitors; as of 17 September 2026 we found none from the Association or from research companies. What exists is national data.
The Ministry of the Environment measured the effect of parasols in its May 2019 paper on promoting their use. The heat index (WBGT) under a parasol is 1 to 3°C lower than in direct sun; at Chiba Zoological Park it was 3°C lower, one warning level down. A parasol blocking more than 99% of solar radiation reduced sweating by about 17% compared with a hat alone. Taking off a jacket cuts heat stress by about 11%, and adding a parasol brings the total to about 20%. On a street without trees, a parasol is worth as much as street trees planted every 10 metres. The ministry concluded that parasols are advisable “regardless of gender” and ran the campaign with the Japan Department Stores Association (79 companies, 201 stores) and the umbrella makers’ association.
A survey by the Men’s Rize clinic chain in April 2025, of 600 men aged 10 to 49, found 17.8% already using a parasol, up 9.8 points from 8.0% two years earlier. The share who had seen a man with a parasol went from 41.5% in 2023 to 48.0% in 2024 and 64.9% in 2025, and 81.8% felt positive about men’s parasols. A national survey by Cross Marketing in May 2025 put parasol use at 47.4% of all respondents, with one man in four.
Mercari’s trend report of 6 July 2026 says purchases of men’s parasols (including rain-or-shine models) peak in July every year, and that July 2025 was up 61% on the previous July, against 7% for women’s parasols. In 2026, April was up 18% and May up 16%, ahead of the previous year. Buyers were most often in their 40s, then 50s, and the most popular brand was mont-bell.
None of these three publications mentions the expo.
Yokohama’s August is 31°C, and the site is outdoors
The Japan Meteorological Agency’s normals for Yokohama (1991 to 2020) give an average daily high of 29.4°C in July, 31.0°C in August and 27.3°C in September. GREEN×EXPO 2027 runs from 19 March to 26 September 2027, so July and August are inside the run in full and September up to the 26th. A horticultural expo is mostly outdoors, and the Association’s own announcement describes the outdoor gardens and flower beds as free to roam without a reservation.
The GREEN×EXPO Association’s visitor transport plan (third edition, July 2026) says shuttle-bus boarding points will get shade roofs as a heat measure, and that the walking route from Seya Station to the site will get shade and mist installations in cooperation with Yokohama City. On 9 July 2026 Metawater announced it would sponsor a heat-countermeasure project to install outdoor drinking-water spots. We have not found an announcement listing rest areas or mist points inside the site as of 17 September 2026, and will add it when one appears.
The visitor rules (first edition 19 March 2026) do not mention umbrellas or parasols. Prohibited items are tents, suitcases and carts, tripods and selfie sticks larger than palm size, and drinks in bottles or cans. Plastic bottles are allowed, and the Association recommends bringing your own bottle. Prohibited conduct includes sitting down or occupying space in a way that obstructs other visitors’ movement or viewing.
Correction (19 October 2026): In “Yokohama’s August is 31°C, and the site is outdoors” we wrote that all three months, July to September, fall inside the run; the run ends on 26 September, so 27 to 30 September do not.