Omachi Temperature by Month
The average annual maximum temperature in Omachi, Nagano Prefecture, Japan is 13°C (55°F), with daytime highs ranging from -1°C (30°F) in January to 26°C (79°F) in August. This page covers monthly averages, day-night differences, and how Omachi compares to cities worldwide.
Omachi Monthly Temperatures
In Omachi, temperatures differ significantly between summer and winter months. Nighttime lows reflect this range, dropping from 17°C (63°F) in August to -9°C (16°F) in January.
The chart below illustrates the average maximum day and minimum night temperatures in Omachi by month:
Daily lows are most common between 4 AM and 6 AM. By 3 PM temperatures reach their daily high, driven by peak solar heating. August, the warmest month of the year, receives 166 hours of sunshine.
The chart below shows the average temperature throughout the year:
Temperature: Omachi vs Japan
The map below shows the annual temperature across Japan. You can also select individual months if you want to compare a specific time of year.
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Omachi vs World: Temperature Compared
Omachi's average annual maximum temperature is 13°C (55°F). To put that in context, here's how it compares to a few well-known destinations:
Rome, Italy averages 20°C (68°F) annually, with reliably warm summers and comfortable winters.
Zermatt, Switzerland averages just 4°C (39°F) annually due to its altitude, with very cold winters and cool summers even at its warmest.
Chicago, USA averages 15°C (59°F) annually — known for extreme seasonal swings, from bitterly cold winters to warm summers.
Melbourne, Australia averages 20°C (68°F) annually — known for unpredictable weather, with four seasons sometimes happening in one day.
Climate temperature data is typically calculated as a 30-year average. This smooths out year-to-year variability and gives a more reliable picture of what a place is actually like, rather than what happened in any single unusual year.
The readings come from a range of sources — land-based weather stations, ocean buoys, ships, and satellites. That data is collected by weather services around the world, then pooled, quality-checked, and averaged to produce the climate records you see here.
Whether a city sits on the coast or deep inland makes a significant difference to its climate. Coastal areas tend to have more stable temperatures year-round — large bodies of water absorb heat slowly in summer and release it gradually in winter, keeping extremes in check. Cities far from the sea don't benefit from that buffer, which is why continental climates tend to have hotter summers and colder winters than their coastal counterparts at the same latitude.
For more on Omachi's weather — including monthly rainfall, sunshine hours, and humidity — visit our Omachi climate page.