Foreign residents in western Japan should remain vigilant as seismic activity continues in the Shimane-Tottori region following a magnitude 6.4 earthquake that struck on January 6, 2026. The Japan Meteorological Agency (JMA) has warned that earthquakes of similar intensity could occur in the coming days, making preparedness essential for all residents in the affected areas.

The initial earthquake, which occurred on January 6 in eastern Shimane Prefecture, registered a seismic intensity of 5-strong (shindo 5-kyō) in both Shimane and Tottori prefectures, according to NHK. This level of intensity can cause considerable shaking, potentially knocking over unsecured furniture and making it difficult to remain standing. While no tsunami warning was issued, the quake marked the beginning of ongoing seismic activity that has kept the region on edge.

As of January 7, aftershocks continue to rattle the area. At approximately 6:39 PM on January 7, another earthquake struck, registering seismic intensity 3 in Yonago City (Tottori Prefecture) and Yasugi City (Shimane Prefecture). The JMA emphasizes that historical patterns in this region show that earthquakes of comparable magnitude to the initial shock can occur following major seismic events, urging residents to maintain heightened awareness and preparedness.

A particular concern from the January 6 earthquake was the observation of long-period ground motion, known as "chōshūki jishin-dō" in Japanese. According to NHK, Sakaiminato City in Tottori Prefecture recorded the highest level of long-period ground motion at "Class 4." This type of seismic wave is characterized by slow, large-amplitude oscillations that can affect structures far from the epicenter. High-rise buildings and towers are especially vulnerable to this phenomenon, as the slow swaying can continue for several minutes and potentially cause damage even in areas that experience relatively modest shaking intensity.

For expats living in tall buildings in the region, understanding long-period ground motion is crucial. Unlike conventional earthquake shaking, these waves can cause furniture to slide across floors, hanging objects to swing violently, and can make it difficult to move safely during the event. Residents of high-rise apartments should ensure that heavy furniture is secured and that evacuation routes remain clear.

Complicating the situation, weather conditions are expected to deteriorate across the region. NHK reports that winter weather patterns will bring snow and strong winds to the San'in region (Shimane and Tottori) on January 8, with the three-day weekend potentially seeing severe weather conditions. The combination of ongoing seismic activity and harsh winter weather creates additional challenges for emergency response and evacuation procedures.

Experts recommend that foreign residents in the affected prefectures take immediate preparedness steps. Ensure emergency supply kits are readily accessible, including water, non-perishable food, flashlights, batteries, and first-aid supplies. Keep important documents and medications in an easily grabbed location. Identify safe spaces in your home, such as under sturdy tables or in doorways, and establish communication plans with family, friends, and employers.

Given the language barriers that many expats face, downloading emergency alert apps with English language support is essential. The Japan Meteorological Agency and local municipal governments provide earthquake early warnings through smartphone systems, but ensuring these notifications are properly configured can make a critical difference in response time.

The current seismic situation serves as a reminder that Japan's earthquake preparedness is not merely theoretical. While the country's infrastructure and building codes provide significant protection, individual preparedness remains the first line of defense. Foreign residents should use this opportunity to review their emergency plans and ensure they understand local evacuation procedures. With meteorologists warning of continued seismic activity and deteriorating weather conditions, now is the time to prepare, not panic.