Climate averages 1991–2020

Nagasaki weather
in January.

A cool, moderately wet month: the coolest and the driest of the year.

Long-term climate patterns, not a forecast for a particular trip.

Average high 9.8°C Daytime mean, January
Average low 6.3°C Night-time mean, January
Rainfall 79 mm 11 days with ≥1 mm
Daylight 10 h Sunrise to sunset, per day
Every month in Nagasaki · average highYear overview

January is a cool month in Nagasaki: daytime highs average 9.8°C and nights cool to about 6.3°C. By daytime temperature it is the coolest month of the year.

Expect about 79 mm of rain on roughly 11 days, which makes January a moderately wet month (the driest month of the year). Daylight, from sunrise to sunset, lasts about 10 h 15 min on an average January day.

The nearest other city in this atlas is Isahaya (18 km away). In January its highs average 9.3°C, 0.5°C cooler than Nagasaki, with 79 mm of rain.

Among the 303 cities listed in Japan, Nagasaki ranks joint 15th of 303 for the warmest January highs and joint 225th of 303 for the driest January (rainfall, lowest first). The mean January high of those 303 cities is 7.0°C; Nagasaki is 2.8°C warmer than that mean.

From January to February, average highs rise by 0.9°C to 10.7°C, and monthly rainfall rises from 79 mm to 100 mm.

The annual picture

January in context

30-year average
Average highAverage low°C
Average daily high and low temperatures by month The same values are available in the monthly table below. Lines show mean daily maxima and minima, not a forecast interval. 05101520253035 JanFebMarAprMayJunJulAugSepOctNovDec

Monthly rainfall

Average total · mm
Average monthly rainfall totalsEach bar is a mean monthly total over 1991–2020. Full numbers are in the table. JanFebMarAprMayJunJulAugSepOctNovDec 4500

Averages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated

Every month, side by side

Nagasaki climate table

1991–2020
Monthly climate averages for Nagasaki, 1991–2020
MonthAverage highHigh / lowAverage lowRainfall mm/monthRain days ≥1 mm/dayDaylight hours/dayDay­light h/day
January, selected 9.8°C6.3°C6.3°C7910.910.310 h
February 10.7°C6.5°C6.5°C10010.211.011 h
March 13.5°C8.9°C8.9°C14912.012.012 h
April 17.4°C12.6°C12.6°C16711.413.013 h
May 21.2°C16.7°C16.7°C19710.813.814 h
June 24.1°C20.4°C20.4°C44416.514.314 h
July 27.4°C24.3°C24.3°C34616.614.114 h
August 29.1°C25.6°C25.6°C18513.713.413 h
September 26.7°C22.8°C22.8°C20211.912.412 h
October 22.3°C18.3°C18.3°C1127.511.411 h
November 17.2°C13.4°C13.4°C1069.110.511 h
December 12.2°C8.6°C8.6°C9210.310.010 h

Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.

Compare places

January in nearby cities

Distance from Nagasaki

Read the numbers correctly

Climate, not a promise.

These patterns help compare months. They cannot tell you the weather on a specific day of your trip.

Sources, method and limits

How these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Nagasaki) is explained once on the Nagasaki year overview and on the Sources, method and limits page.

Isahaya lies in the same rainfall cell, so its rainfall figures are identical to these; temperatures differ because they come from smaller 0.1° cells.