Tokyo monthly typhoon prep: June through October

A midterm guest's first Tokyo typhoon arrives on a Wednesday in early September. The 気象庁 (Kishōchō — Japan Meteorological Agency, JMA) names it Typhoon No. 14. The Yahoo Weather app puts a red icon on the next 72 hours. The convenience store across the road runs out of bottled water by 8pm Tuesday. By 10pm Wednesday, JR East has posted a 計画運休 (keikaku unkyū — planned suspension) for the Yamanote Line starting 6am Thursday.

None of this is improvised. JMA, your ward office, and your operator each play a defined role on a published schedule. Your job is to read the schedule and act on each window. Below is the schedule.

The peak season runs late August to mid-October, with smaller storms from mid-June. Most stays of 30 to 90 days will see one or two named typhoons reach Honshū. Most of those weaken to a tropical depression before landfall. One in three years, a category-3 or category-4 storm tracks within 100km of Tokyo Bay and triggers the rules described here in full.

---

City, ward, building: who tells you what

Three sources publish typhoon information for your address. Each owns a different layer.

The city level is JMA. The agency runs the bilingual site at jma.go.jp/bosai/map.html and the Yahoo Weather app, both in Japanese and English. JMA names the storm, predicts the track, and issues the 注意報 (chūihō — advisory), 警報 (keihō — warning), and 特別警報 (tokubetsu keihō — emergency warning) bulletins. The colour code is yellow for chūihō, red for keihō, purple for tokubetsu keihō. Keihō means real damage is likely. Tokubetsu keihō is issued maybe once a decade and means once-in-fifty-years conditions are imminent.

The ward level is your 区役所 (kuyakusho — ward office). The ward owns evacuation centres, hazard maps, and the local broadcast. Each ward publishes a 防災マップ (bōsai mappu — disaster prevention map) showing which schools and community halls open as 避難所 (hinanjo — evacuation shelters). Setagaya's map is at city.setagaya.lg.jp/mokuji/kurashi/13/index.html. Bunkyō posts at city.bunkyo.lg.jp/bousai. Shibuya runs city.shibuya.tokyo.jp/anzen. Search "[ward name] 避難所" if you cannot find the page directly. Save the PDF to your phone before the storm, because cell data slows during a watch.

The building level is your operator or landlord. They control the shutters, the rooftop drainage, and the emergency phone tree. Furnished mid-term operators publish a 24-hour emergency contact line in the move-in handbook. halfkey runs one. Oakwood and Citadines run one. Sakura House and most cheaper monthlies run a daytime line that voicemails after 6pm. Find the number now and put it in your phone. The night a typhoon lands is the wrong night to learn whose line is staffed.

Seventy-two hours out: stocking and rebooking

JMA's keihō goes up roughly 72 hours before the closest pass. This is the window where a midterm guest still has options.

Buy three days of bottled water and shelf-stable food at the konbini before noon on the day the keihō posts. Aftermarket runs out of water by mid-afternoon and bread by evening. Konbini do not restock during a warning, because their truck routes pause. The shortage is brief, usually 36 hours, but it overlaps the storm.

Charge every battery you own. Power on Tokyo's grid stays up in 95 percent of typhoons, but the unlucky 5 percent are clustered in the categories you care about. Charge phones, laptops, the mobile router if you brought one, and a small power bank if you have one. A 10,000mAh bank is ¥2,400 at any Bic Camera and pays for itself in one outage.

Cancel your travel for the predicted landfall day plus one. JR East and Tobu and Tokyu publish 計画運休 announcements through their mobile sites and the Yahoo Transit app, usually 24 hours before suspension. The Tokaidō Shinkansen pauses at sustained winds above 25m/s near the tracks. Narita Express and the airport limousine bus stop when the airport closes, and Narita closes when sustained winds at the runway exceed about 30m/s. Domestic carriers (ANA, JAL, Peach) waive change fees the day a tokubetsu keihō or a category-3 typhoon path goes up. Rebook to the next clear day; you will not be the only one trying.

Read your apartment's 防災のしおり (bōsai no shiori — emergency handbook) section on shutters, balcony objects, and window film. Every operator publishes one. Most furnished units include a brief paragraph on what the building will close and what you must close. The handbook also lists the building's nearest hinanjo. This may not match the ward office map, because wards rezone after redrawing flood lines.

Twelve hours out: lockdown

Twelve hours out, the predicted track narrows to a 50km error band. Move from preparation to lockdown.

Bring everything off the balcony into the apartment. Drying racks, plant pots, slippers, the futon airer. A 4kg pot becomes a window-shattering projectile at 35m/s. The same rule applies to bicycles in the stairwell of an older walk-up apaato. The stairwell vents to the street, so wind picks up there too. If you cannot bring the bike inside, rope it to the railing with whatever cord you have. Operators in newer manshon often lower a metal shutter over the balcony bay. You may hear it descend on a switch from the property-management office.

Tape the inside of single-pane windows with the X pattern. Two diagonal strips of brown packing tape across each pane. Most modern windows are double-glazed and do not need taping. Some 1985-1995 manshon still have single panes in the bedroom or kitchen. The tape does not stop the glass from breaking; it keeps the shards together if it does. ¥220 for a roll at any Daiso.

Fill the bathtub. Tokyo water rarely cuts during typhoons. Pressure can drop in older buildings if the rooftop tank pump loses power for 4 to 8 hours. A full tub gives you 200 litres for the toilet flush. That is the use case that matters.

Close all windows. Tape the cracks if you feel a draft. The closed-window rule reverses Tokyo's normal humidity doctrine. See Tokyo apartment heating and mold, the resident rules on why airflow normally matters. During a typhoon, sealed wins. Run the aircon on dry mode for two hours after the storm passes; it pulls the humidity back down.

Reading the JR shutdown notice

Tokyo's rail network publishes 計画運休 hours in advance, not at the moment of suspension. The notice appears on the operator's mobile site (jreast.co.jp, tokyometro.jp, tokyu.co.jp), on the Yahoo Transit app, and on the LED boards at every station.

The Yamanote Line typically pauses last and resumes first. It runs a tight loop with frequent stops, and JR East prioritises the inner-ring service. The Sōbu, Chūō, and Yokohama lines pause earlier. They cross more grade-level crossings and unprotected viaducts. Lines that share track with Tokyo Metro (Hibiya, Tōzai, Chiyoda) follow Metro's slower-to-pause schedule. They resume on whichever upstream line clears last. The Shinkansen is the most predictable: a category-3 storm on the Tōkaidō line pauses Tokyo–Nagoya for 6 hours, often 12.

If you are in another ward when the keihō goes up, leave by the second-to-last announced train. The last one may not run. Trains that do run honour their printed schedule until the announced suspension hour, then stop wherever they are. Crews walk stranded passengers to the next station and lock the train on the line. You do not get a refund and you do not get a substitute bus. Cabs disappear by 1am.

What your operator's emergency line actually does

In a category-4 typhoon, the on-call coordinator at your operator handles three jobs.

First, they answer the phone for unit failures. Water entering the unit, an elevator stranding you between floors, a power cut, a front door that fails to lock. Most operators run a 5 to 30 minute response time on these. They do not dispatch in the middle of a tokubetsu keihō. They call the building manager, who lives onsite or within a 10-minute radius. The manager walks the building once the wind drops below 20m/s.

Second, they triage unit problems versus building problems. A leaking shutter is the building's problem and routes to the landlord's vendor. A broken aircon mounting bracket on the balcony is the unit's problem and routes to the operator's vendor. The triage matters. Building problems usually wait for the next morning's daylight inspection. Unit problems sometimes get same-night service.

Third, they coordinate with the city if the building goes uninhabitable. The rooftop tank loses pressure for more than 12 hours. A window blows in and the unit takes on rain. The operator offers a different unit in the same portfolio. Or they arrange a hotel for two nights. Your operator's handbook should write this path explicitly. Some smaller operators handle it case by case. Read your handbook before the storm so you know which version your operator runs.

The emergency line is not a 24-hour concierge. They will not order you food, recharge your phone, or check the weather for you. They handle property failures and bodily safety, in that order.

When the box is full: what does not work in a typhoon

Yamato and Sagawa pause delivery the morning the keihō posts. Amazon Prime same-day suspends. Uber Eats and Wolt go offline when the city issues a heavy-rain warning, because the courier insurance lapses above 50mm/h rainfall. Plan the food run on the 72-hour side, not the 12-hour side.

Konbini stay open through most warnings. Their truck routes pause for 24 hours. Shelves go bare in this order: bottled water, bread, instant ramen, energy drinks. The microwave food (bentō, onigiri) is restocked twice daily under normal rotation. Expect one rotation, not two, on a typhoon day.

ATMs at konbini run on the building's power and remain online during the storm if the power holds. Bank-branch ATMs close with the branch at 6pm, and many do not reopen until two business days after the storm clears.

---

Walk the apartment before the keihō posts

Find the operator emergency number in the move-in handbook and save it as a contact. Write the building name and address in roman letters under the contact, because dispatch may need to relay it to a non-bilingual driver.

Walk the balcony once and list every loose item. A photo on your phone is enough. The list becomes your 12-hour checklist.

Identify the nearest hinanjo from your ward's bōsai mappu. Save the PDF offline. Walk the route in clear weather, because the route looks different at 70mm/h rainfall and a 25m/s gust.

Check the windows. If any pane is single-glazed, buy one roll of brown packing tape from Daiso and keep it in the kitchen drawer. You will not have time to shop in the 12-hour window.

Set Yahoo Weather's typhoon alert to push to your lock screen. The English app pushes JMA's bulletins automatically. The Japanese app pushes them slightly faster, by a few minutes, because it skips the translation step.

The first time you do this, it takes an evening. After that the routine takes 20 minutes per storm. The cost of skipping it is a flooded floor, a broken window, or a night on a station bench. The train you planned to take will not run.