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Yaizu weather by month: averages, rainfall & climate trends

Average temperatures in Yaizu follow a clear seasonal rhythm, rising and falling by 19.1°C over the course of the year. The heavier rain months run from April to October. Yaizu weather by month: average temperatures, rainfall, extremes and how the climate has changed since 1940.

Today vs average

+2.1°Chigh above average

22° / 19°Today
20° / 17°Average
see today in detail →

How it's changed

+1.9°Caverage temperature, 2016–2025 vs 1940–1949average temperature vs 1940–490frost days a year now (2016–2025) · 2 in the 1940sfrost days a year · 2 in the 1940s21days above 30°C a year now (2016–2025) · 1 in the 1940sdays above 30°C · 1 in the 1940s+1.9°C vs the 1940s · see how it's changed →
Weather by montha typical year, averaged over the full recordJanuary, rain 85 mmhigh 10°low 6°February, rain 109 mmhigh 10°low 6°March, rain 178 mmhigh 13°low 8°April, rain 203 mmhigh 17°low 12°May, rain 237 mmhigh 20°low 16°June, rain 306 mmhigh 23°low 20°July, rain 266 mmhigh 27°low 24°August, rain 216 mmhigh 28°low 25°September, rain 265 mmhigh 26°low 23°October, rain 229 mmhigh 21°low 18°November, rain 148 mmhigh 17°low 13°December, rain 85 mmhigh 12°low 8°wettest month June, 306 mm · 2,328 mm a yearsee month by month →

Right now

What it's doing today vs the historical average for this date.
Light rain

Right now

20.2°

22°feels like
90%humidity
19°dew point
13 km/hfrom NE
UV index0.2
sunrise06:01sunset16:59day length10h 58m
MonLight rain22°19°
TueOvercast24°17°
WedMostly clear21°14°
ThuOvercast20°13°
FriOvercast20°14°
SatClear20°14°
SunMostly clear18°10°

On this date: October 25

Today (forecast)
22° / 19°
Average for October 25
20° / 17°

High above average · +2.1°C

  • Highest since 1940: 24.4° · 2010
  • Lowest since 1940: 10.3° · 1982
  • One year ago: 20° / 18°

Every October 25 in history, coldest to hottest

▲ Daily highs▼ Daily lows

Dots show daily highs (top) and lows (bottom) for each October 25 on record (n = 87). Outlined dots are today's forecast.

Area we sample

Each city's history comes from one ERA5 grid cell, about 28 km across, shown by the dashed box. Near mountains or coasts, conditions can vary across the cell.

Location & data

Historical weather for Yaizu is sampled from the ECMWF ERA5 reanalysis at 34.87°N, 138.32°E, with daily records since 1940.

Coordinates
34.87°N, 138.32°E
Time zone
Asia/Tokyo
Period
1940–2026
Data source
ERA5 (ECMWF)

Last 30 days

27 of the last 31 days were warmer than the historical average for that date. Average difference: +1.7°C.

Each bar is one day, from morning low to afternoon high. Warm-colored bars are days whose mean ran above average; cool bars ran below. The dot inside the bar is the daily mean. The shaded band is the typical 10–90% range expected for that date. Average = the day's mean temperature averaged across every year of record (1940–2026) for that calendar date.

This date over the years

One dot per year, showing the mean temperature on this calendar date. Dots are warmer or cooler than the long-term average (dashed line); the shaded band is the typical 10–90% range, and the highlighted dot is today's forecast. Based on ERA5 reanalysis: modelled estimates, not station readings.

Weather by month

Average temperatures and rainfall for each month: a typical year, from the full record.

Climate overview

The warmest month is August, with typical afternoon highs of 28.1°C and nights around 25.3°C. On about 130 nights a year, the temperature never drops below 20°C. At the other extreme, January brings afternoon highs of about 9.8°C and typical overnight lows of 5.5°C.

Yaizu picks up roughly 2,328 mm a year, with a peak of 306 mm in June and as little as 85 mm in January. Precipitation falls on roughly 135 days in a typical year.

Comparing the record's first decade with its most recent one, Yaizu now averages 1.9°C warmer than it did in the 1940s. The count of days past 30°C has risen from roughly 1 a year to 20 between the record's first and last decades.

Climate graph (climograph)

August is the warmest month, January the coolest: a yearly swing of 19°C. Wettest month: June (~306 mm). Whole year averages ~2,328 mm of rain.

Bars = average monthly rainfall (right axis). Lines = average daily high and low (left axis). Average = each month's value averaged across every year of record (1940–2026).

Rainy days by month

About 135 rainy days a year: most in September (~15), fewest in December (~6).

Bars = average number of days with ≥ 2 mm per month. Hover for the monthly rainfall total.

Monthly wind

Average daily peak wind at 10 m, by month.

Monthly solar energy

Average daily incoming solar energy in megajoules per square metre: the record's own proxy for how sunny the month is.

Yaizu month by month: what to expect

Typical conditions for each month, averaged across the full record (since 1940). Daylight is the time from sunrise to sunset. Highest and Lowest are the most extreme values in the ERA5 dataset (modelled since 1940), so they can differ from official weather-station readings.

MonthAvg highAvg lowRainRainy daysDaylightHighestLowest
January9.8°5.5°85 mm69.9 h19.4° (1969)−1.2° (1997)
February10.3°5.7°109 mm810.7 h20.5° (2024)−2.0° (1981)
March13.0°8.2°178 mm1111.7 h21.6° (2023)0.5° (1941)
April16.9°12.4°203 mm1112.9 h24.3° (1973)4.4° (1965)
May20.4°16.5°237 mm1213.8 h26.1° (2019)9.8° (1991)
June23.3°20.3°306 mm1514.3 h30.9° (2011)14.0° (1969)
July26.8°23.9°266 mm1514.1 h33.6° (2024)18.1° (1976)
August28.1°25.3°216 mm1513.3 h34.6° (2020)21.0° (1956)
September25.8°22.9°265 mm1512.2 h32.2° (2024)16.5° (1980)
October21.4°18.2°229 mm1211.1 h28.7° (2024)9.6° (1997)
November17.1°13.4°148 mm910.1 h25.2° (2024)3.8° (1970)
December12.3°8.2°85 mm69.7 h22.5° (2004)0.6° (1947)

How it's changed

Year-by-year signals from 1940 to today.

Climate stripes

Annual mean shifted from 1940–1949 to 2016–2025 by +1.9°C.

Each vertical stripe is one year. Color encodes how much that year's annual mean differed from the long-term average. Average = each year's annual mean compared to the average of all years (1940–2026). cooler ← → warmer

Annual mean temperature

Long-term trend: +0.19°C per decade.

One point per year, showing the temperature averaged across the whole year. The dashed line is the least-squares long-term trend. Based on ERA5 reanalysis: modelled estimates, not station readings.

Seasonal warming

Dec–Feb is warming fastest: +0.20°C per decade.

Each faint line is one three-month period's average per year; the bold dashed line is its long-term trend. Different parts of the year often warm at different rates. Based on ERA5 reanalysis: modelled estimates, not station readings.

Hot days vs frost days

Days ≥ 30°C per year: 1.4 early in the record → 20.5 recently. Frost days: 2 → 0.

Thin lines are raw yearly counts; thick lines are the smoothed trend that removes year-to-year noise. The hot-day threshold is auto-picked per city so the line actually moves. Average = a centered 5-year rolling average to smooth weather noise.

Yearly hot & cold extremes

Hottest day since 1940 in 2020, coldest in 1981: 34.6°C / −2.0°C.

One point per year: the single hottest and coldest day recorded that year.

Annual rainfall

~2,328 mm/year on average. Last decade: +5% vs that average. Long-term trend: +42 mm per decade.

One bar per year of total rainfall. Dashed line is the long-term average. Average = the average annual rainfall across every year of record (1940–2026).

Day-by-day grid

Each tiny square is one calendar day across the full record, about 30,000 days per city. Use the mode switch above the chart: Anomaly colors each day by how far it ran from the historical average for that date (red = warmer, blue = cooler), Daily mean temp shows the absolute mean temperature for the day (useful to see seasons and heatwaves), and Precipitation shows daily rainfall (useful to spot wet/dry seasons and droughts). Average = the long-term average for that calendar date (1940–2026).

Frequently asked questions about Yaizu

Which is the warmest month in Yaizu?
On long-term average, the warmest month in Yaizu is August (mean daily temperature of about 26.6°C) and the coolest is January (about 7.5°C).
How does today's temperature in Yaizu compare to the historical average?
On October 25, 2026, Yaizu is forecast to reach a high of 22.1°C and a low of 19.3°C. The long-term average for this date (the full record since 1940) is a high of 20.0°C and a low of 16.7°C, so today's high is 2.1°C warmer than that average.
How much has Yaizu warmed since 1940?
Comparing the first decade of the record (1940–1949) with the most recent (2016–2025), the annual mean temperature in Yaizu is about 1.9°C warmer.
How much does it rain in Yaizu?
Yaizu receives about 2,328 mm of precipitation per year on long-term average, with June typically the wettest month.
What is the average temperature in Yaizu?
Over the full record (since 1940), the annual mean temperature in Yaizu is about 16.8°C. The warmest month is August and the coolest is January.
What are the average temperatures in Yaizu by month?
Average daily highs and lows for each month in Yaizu (°C, full record since 1940): January 10°/6°, February 10°/6°, March 13°/8°, April 17°/12°, May 20°/16°, June 23°/20°, July 27°/24°, August 28°/25°, September 26°/23°, October 21°/18°, November 17°/13°, December 12°/8°.
What is the weather like in Yaizu in summer?
June to August is summer in Yaizu, and it is wet and warm. It warms from 23°C by day and 20°C at night in June to 28°C and 25°C in August. Rain is steady at around 263 mm a month, spread over roughly 15 days. No season is wetter.
What is the weather like in Yaizu in winter?
In winter, December through February, Yaizu is on the cool side. Afternoons run 10–12°C and nights 6–8°C; January is the coldest month. Rain falls on about 7 days a month, adding up to around 93 mm. No season is drier.
What is the weather like in Yaizu in spring?
Spring in Yaizu (March to May) is wet and fairly mild. It warms from 13°C by day and 8°C at night in March to 20°C and 16°C in May. Rain is steady at around 206 mm a month, spread over roughly 11 days.
What is the weather like in Yaizu in autumn?
Autumn in Yaizu (September to November) is wet and mild. September is still 26°C by day and 23°C at night; by November it is down to 17°C and 13°C. Rain eases through the season: 15 rainy days and 265 mm in September, 9 days and 148 mm in November.
How many days a year does it rain in Yaizu?
On long-term average, Yaizu has about 135 days a year with at least 2 mm of rain or snow. The annual total is roughly 2,328 mm.

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