What Does Hong Kong's No. 8 Signal Mean? How Does It Correspond to Mainland China's Warning Systems?
TyphoonSays·防御问答 · Early warning signals · 更新 at 2026-07-16
What is Hong Kong's No. 8 Signal?
The "No. 8 Signal" is a highly representative level in Hong Kong's tropical cyclone warning system, officially known as the "No. 8 Gale or Storm Signal." When the Hong Kong Observatory issues this signal, it means that gale or storm force winds are affecting or are expected to affect Hong Kong at sea level, with sustained wind speeds reaching 63 to 117 km/h, and gusts potentially exceeding 180 km/h.
For Hong Kong residents, the No. 8 Signal is not just meteorological data; it acts as a "switch" that changes the rhythm of social operations. Once the No. 8 Signal is hoisted, most schools suspend classes, non-essential industries typically stop work, public transport (such as the MTR and buses) may reduce services or suspend operations, and the stock market closes. This mechanism aims to give residents sufficient time to return home and seek shelter before severe weather arrives, reducing the risk of outdoor exposure. It is important to note that the No. 8 Signal is divided into four directions: Northwest, Southwest, Northeast, and Southeast, indicating the primary direction from which the gale is blowing. This helps the public identify the areas where wind and rain will be strongest.
Correspondence with Mainland China's Typhoon Warnings
Many people from Mainland China are curious: what color warning in the Mainland corresponds to Hong Kong's No. 8 Signal? Although the design logic of the two warning systems differs—the Mainland focuses on impact predictions for the next 24–48 hours, while Hong Kong focuses on immediate or short-term wind threats—we can draw a rough comparison based on wind force levels.
According to the National Standard "Tropical Cyclone Grades" by the China Meteorological Administration (CMA), typhoons are classified by the maximum wind force near the center. The sustained wind speed corresponding to Hong Kong's No. 8 Signal (63–117 km/h, i.e., approximately 17.5–32.5 m/s) roughly covers the upper limit of a Tropical Storm to a Severe Tropical Storm, and even touches the lower threshold of a Typhoon.
In terms of warning colors, it generally corresponds to the Mainland's Yellow Typhoon Warning or Orange Typhoon Warning:
- Yellow Typhoon Warning: Indicates that a tropical cyclone may affect the area within 24 hours, with average wind forces reaching Level 8 or above. This is relatively close to the wind threshold of the No. 8 Signal.
- Orange Typhoon Warning: Indicates that a tropical cyclone may affect the area within 12 hours, with average wind forces reaching Level 10 or above. If the No. 8 Signal is accompanied by stronger gusts or a more urgent timeframe, its hazard level can be compared to an Orange Warning.
Please note that this correspondence is not an absolutely precise mathematical conversion, as there are differences in geographical environments, building wind-resistance standards, and defense priorities between the two regions. Standards may vary by location; please refer to the announcements issued by local governments.
Defense Recommendations and Action Guide
Regardless of your location, when facing wind and rain threats of this magnitude, the core principles are "Avoidance" and "Prevention."
- Stay Indoors: Do not go outside. Stay away from windows and glass doors to prevent injury from shattering glass.
- Secure Windows and Doors: Check that all windows and doors at home are tightly closed. Clear flower pots and debris from balconies to prevent objects from falling from heights.
- Stock Up on Supplies: Prepare adequate drinking water, food, power banks, and common medications in advance to cope with potential water and power outages.
- Monitor Information: Closely follow the latest guidelines issued by local meteorological departments and do not trust rumors.
Real-time typhoon tracks can be queried at TyphoonSays (taifengshuo.com)
This article is typhoonsay's original copy content, and the local policy standards are based on the local government's latest release.