Climate and monthly weather forecastNagano, Japan

The climate of Nagano

Due to its geographical location in the inland area of Japan, Nagano city has a Humid continental climate with no dry season and warm summers, according to the Köppen climate classification. Both the climate and geographical position of the city greatly affect the weather patterns observed throughout the year.

Nagano experiences a broad contrast between high and low temperatures. The highest temperatures are observed in summer, specifically in the month of August, ranging from 25.7°C (78.3°F) to 31°C (87.8°F), while the coldest period is winter, particularly during January, with temperatures fluctuating between -4.1°C (24.6°F) and 3.5°C (38.3°F). The shift in temperature from one extreme to the other is noticeable as the seasons transition from spring to winter.

In terms of rainfall, the city encounters a regular and abundant rain with the most significant rain events occurring from June to September. June stands out with 109mm (4.29") of rain, while July and September also experience heavy rainfall exceeding 100mm (3.94"). December and February have the least rainfall, measuring 46mm (1.81") and 44mm (1.73") respectively.

Unique weather conditions in Nagano include a significant amount of snowfall, primarily occurring from December to March. The heaviest snowfall is reported in January with 980mm (38.58") of snow.

Relative humidity in Nagano stays relatively constant throughout the year, ranging between 61% and 78%. The sunniest months are from April to August, with sunshine hours reaching up to 14.6 hours per day in June.

The best time to visit Nagano

Given its climatic variations, the ideal time to visit Nagano for outdoor activities and sightseeing is predominantly in the spring from March to May. During this period, the city experiences mild temperatures ranging from 9.5°C (49.1°F) to 22.5°C (72.5°F) with an average rainfall around 50mm (1.97") to 75mm (2.95") per month, and an average of 12 to 14 daylight hours.

The worst time to visit Nagano

Given the severe winters with temperatures dipping as low as -4.1°C (24.6°F) in January, and substantial snowfall reaching 820mm (32.28") to 980mm (38.58") from December to February, these months are generally regarded as the least favorable for visitors. However, this period could be of interest to those who enjoy winter sports or want to witness the unique beauty of a snow-covered landscape.

Spring weather in Nagano

Spring in Nagano, commencing in March and enduring up to May, signifies a welcome change from the harsh winter. The rising temperatures oscillate between -0.8°C (30.6°F) and 22.5°C (72.5°F) and average rainfall increases from 59mm (2.32") in March to 75mm (2.95") in May. By May, daylight hours have increased to 14.1 hours daily, offering more time for outdoor activities and sightseeing.

Summer weather in Nagano

Summers in Nagano, extending from June to August, are quite warm with temperatures reaching as high as 31°C (87.8°F). Humidity and rainfall are also at their peak during this period, with June receiving 109mm (4.29") of rain and July having a relative humidity of around 74%. Despite these conditions, summer days are long in Nagano, with 14.4 to 14.6 hours of daylight in June and July.

Autumn weather in Nagano

With temperatures ranging between 9.7°C (49.5°F) and 25.6°C (78.1°F), Autumn in Nagano, that stretches from September to November, is marked by cool and comfortable days. Rainfall begins to reduce, decreasing from 129mm (5.08") in September to 44mm (1.73") by November. Meanwhile, daylight hours start to shorten, falling from 12.4 hours in September to 10.2 in November.

Winter weather in Nagano

Winter in Nagano, from December to February, is synonymous with freezing temperatures and heavy snowfall. Subzero temperatures ranging from -4.1°C (24.6°F) to 4.7°C (40.5°F) are common, with hefty snowfall reaching up to 980mm (38.58") in January. Despite the harsh conditions, the city enjoys sparkling sunshine for 4.4 hours a day in December.

Weather in January

January marks the start of the year in Nagano, Japan with comparatively lower temperatures and significant levels of snowfall. The high average temperature for the month registers at 3.5°C (38.3°F), while the low plunges to -4.1°C (24.6°F). Weather in January »

Weather in February

It continues to be cold in Nagano, Japan in February, though the snowfall decreases compared to January. The average snowfall of 820mm (32.28") marks a reduction as this winter month unfolds. The chill in the air still persists, but with relatively milder temperatures, the city begins to anticipate the arrival of spring. Weather in February »

Weather in March

With March, the departure of the winter chill gradually begins in Nagano, Japan. The snowfall substantially reduces to an average of 270mm (10.63"), highlighting a clear shift in weather patterns. Warming temperatures connote the oncoming change of season, inducing a freshness in the air. Weather in March »

Weather in April

April witnesses a judicious mix of rainfall and warmth, paving the way for the full bloom of spring in Nagano, Japan. The snowfall essentially becomes a rare sight, standing at a minimal average of 30mm (1.18"). The temperature sustains a steady climb, making the days pleasantly warm and the nights mildly cool. Weather in April »

Weather in May

May brings with it an influx of warm weather and increased levels of rainfall in Nagano, Japan. The average rainfall amplifies to 75mm (2.95"), marking the onset of the city's rainy season. The temperatures continue their upward trend, resulting in a warm and humid atmosphere across the city. Weather in May »

Weather in June

June stands out as the month with the longest daylight hours in Nagano, Japan. The highest level of daylight graces the city with an average of 14.6 hours per day. As summer begins to set in, the temperature soars, and the instances of rainfall amount to a higher frequency. Weather in June »

Weather in July

July is typically the hottest month in Nagano, Japan with average temperatures reaching up to 29.1°C (84.4°F). The city groans under the burden of the summer heat, and the humidity levels rise in parallel, further exacerbating the hot conditions. Weather in July »

Weather in August

August continues the trend of soaring temperatures in Nagano, Japan, although comparatively cooler than July. The temperatures level off slightly, but the humidity persists, retaining the summer heat wave. This period highlights a decrease in rainfall, yet the occasional shower can cool the air momentarily. Weather in August »

Weather in September

September in Nagano, Japan presents itself with relatively high rainfall and a decrease in temperatures. The month trots in a higher average rainfall of 129mm (5.08"), the highest in the latter half of the year. This increased rainfall brings about a freshness to the city while also ushering in the autumn season. Weather in September »

Weather in October

October begins to bid adieu to the high rainfall season in Nagano, Japan, laying the groundwork for a crisp autumn climate. The rainfall decreases, and the temperature takes a significant dip, further emphasizing the arrival of fall. Weather in October »

Weather in November

Embracing the heart of fall, November in Nagano, Japan observes a further decrease in temperature. Persistent chilly winds and the first few flurries of snow signal the imminent approach of winter. The city is draped in a blanket of warm colors with leaves ranging from vivid reds to burnt oranges. Weather in November »

Weather in December

December rings in the winter season in full swing in Nagano, Japan. The city returns to the cool temperatures of the year's onset, with average temperatures sliding down to 6.8°C (44.2°F) and an increased snowfall of 450mm (17.72"). Weather in December »