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On Wednesday, October 21, 2026, rain will fall widely across Nagasaki Prefecture, with heavy rain expected until around noon. According to the Nagasaki Local Meteorological Observatory, there is a possibility of intense rain accompanied by thunder in the southern and northern parts of the prefecture, as well as in Iki, Tsushima, and Goto regions. The weather is expected to change to cloudy or clear from the afternoon onward. In Nagasaki City, the forecast predicts clear skies in the morning followed by rain, then clearing again in the evening. The improvement in weather at night makes it important to prepare appropriate clothing and umbrellas when going out. This article provides a detailed explanation of the weather changes by region and the timing of rainfall throughout the day in Nagasaki Prefecture. [1] [2]

Overall Weather Forecast for Nagasaki Prefecture on October 21

On Wednesday, October 21, 2026, rain is expected to fall widely across Nagasaki Prefecture, with heavy rain continuing until around noon, followed by clearing skies at night. The heavy rain until noon may be accompanied by thunder, requiring caution. The weather is expected to improve overnight, with clear skies spreading. This information is based on reports from Nagasaki International Television on October 20. The forecast highlights the extent and timing changes of rain across the prefecture. Announcements from the Nagasaki Local Meteorological Observatory support these details. The forecast of widespread rain during the day and clearing at night will affect residents' daily lives, making prior preparation necessary. [1]

The weather on this day represents a shift from clear skies in the preceding days to rain, which may impact outings and transportation. The heavy rain until noon, sometimes accompanied by thunder, calls for caution during outdoor activities. Since the weather is expected to clear by night, nighttime outings are considered relatively safe, but attention to daytime weather changes is important. Nagasaki Prefecture's meteorological conditions occur during a seasonal transition period, when sudden weather changes are common. This forecast reflects those characteristics. [1]

Detailed Weather Forecast by Region

According to the weather forecast issued by the Nagasaki Local Meteorological Observatory at 5 p.m. on October 20, 2026, rain will fall in the southern and northern parts of Nagasaki Prefecture, as well as in Iki, Tsushima, and Goto regions, with conditions expected to change to cloudy after noon. Particularly from morning to before noon, there is a possibility of intense rain accompanied by thunder. The timing of rain onset and thunder occurrence varies by region, with Iki and Tsushima possibly experiencing intense rain with thunder until dawn. This information is based on reports from FNN Prime Online. [2]

Furthermore, the latest weather forecast issued at 5 a.m. on October 21, 2026, indicates that the southern region will experience cloudy skies turning to rain from morning until early afternoon; the northern region will have rain changing to cloudy by evening; Iki and Tsushima are expected to change from rain to clear skies; and Goto will shift from rain to cloudy. These regional differences in rain timing and weather changes are confirmed. Such detailed forecasts by region provide important information for residents to plan appropriate measures according to local weather. The latest announcements from the Nagasaki Local Meteorological Observatory allow understanding of each area's weather characteristics. [4]

Hourly Weather Changes in Nagasaki City

The weather in Nagasaki City on October 21, 2026, is expected to change from clear skies in the morning to rain, with rain continuing from noon through the afternoon. Clearing is forecast from the evening onward. Specifically, rain is expected to begin around 9 a.m. and continue until about 3 p.m., after which clear skies will spread. Precipitation is expected to be heavier in the morning and decrease in the afternoon. This information is based on Yahoo! Weather and Disaster data. Understanding the hourly weather changes in Nagasaki City can assist in planning outings, commuting, and school attendance. [3]

These hourly weather changes are important information for residents of Nagasaki City. Although it will be clear in the morning, rain will begin in the afternoon, so carrying an umbrella is necessary. Since the weather will clear again in the evening, nighttime outings are expected to be relatively comfortable. Temperatures will reach around 26 degrees Celsius, making it a comfortable autumn day. Adjusting clothing according to weather changes is also necessary. Nagasaki City's meteorological conditions are distinctive compared to other areas in the prefecture, so utilizing weather information with awareness of regional differences is recommended. [3]