Aomori weather by month

TL;DR

At the Aomori (青森) weather station, which we use for Aomori, the warmest month is August (average high 27.8 °C) and the coldest January (average low −3.5 °C), averaged over 1991–2020. The wettest month is December (155 mm of rain). Aomori's quietest month for visitors in 2025 was January.

A mountain stream at Oirase, Aomori
A mountain stream at Oirase, Aomori. Photo by veronica111886 on Pixabay.

Aomori weather by month

Averages for 1991–2020 at the Aomori (青森) weather station, copied from our Aomori page, next to each month's share of Aomori's guest nights (Japan Tourism Agency, 2025). These are long-term averages, not a forecast.

Aomori: average weather by month, 1991 to 2020, and share of 2025 visits
MonthAverage highAverage lowRainRainy daysDaylight on the 15thShare of 2025
January1.8 °C−3.5 °C140 mm21.9 days9 h 35 min6.2%
February2.7 °C−3.3 °C99 mm18.1 days10 h 40 min6.5%
March6.8 °C−0.8 °C75 mm14.1 days11 h 55 min6.4%
April13.7 °C4.1 °C69 mm10.6 days13 h 20 min7.7%
May18.8 °C9.4 °C77 mm9.6 days14 h 30 min8.7%
June22.1 °C14.1 °C75 mm8.3 days15 h 5 min8.3%
July26.0 °C18.6 °C130 mm9.1 days14 h 50 min9.2%
August27.8 °C20.0 °C142 mm9.6 days13 h 50 min11.5%
September24.5 °C15.8 °C133 mm10.3 days12 h 30 min9.3%
October18.3 °C9.1 °C119 mm12.8 days11 h 10 min10.4%
November11.2 °C3.4 °C137 mm16.7 days9 h 55 min8.7%
December4.5 °C−1.4 °C155 mm21.2 days9 h 15 min7.2%

Golden hour and sea temperature

Evening golden hour is our calculation for the 15th of each month of 2026: the time the sun takes to go from 6° above to 4° below the horizon (there is no official definition). The sea figure is the 1991–2020 average sea surface temperature at the open-sea point nearest the weather station (NOAA OISST).

Aomori: golden hour and sea temperature by month
MonthEvening golden hour (15th)Sea surface
January1 h 1 min10.2 °C
February0 h 56 min8.2 °C
March0 h 53 min7.6 °C
April0 h 54 min7.9 °C
May0 h 58 min10.8 °C
June1 h 2 min15.2 °C
July1 h 0 min19.1 °C
August0 h 56 min22.6 °C
September0 h 53 min22.3 °C
October0 h 54 min19.1 °C
November0 h 59 min15.2 °C
December1 h 3 min12.3 °C

The quietest and busiest months

In 2025, January was Aomori's quietest month (6.2% of the year's guest nights): average high 1.8 °C, average low −3.5 °C, 140 mm of rain. August was the busiest (11.5%): average high 27.8 °C, average low 20.0 °C, 142 mm of rain. The figures do not show that the weather makes a month busier or quieter, so we do not say it does.

What these figures are

One weather station stands for Aomori; places nearby can differ, especially by height or distance from the sea. For the full picture of Aomori, including regions and holidays, see our Aomori page; for other places, the visual guides and golden hour by place.

Where the Aomori (青森) weather station is: 40.822° N, 140.768° E. Outline of Japan from Natural Earth (world-atlas), simplified; small islands may not show.

Key takeaways

  • Warmest month: August (average high 27.8 °C); coldest: January (average low −3.5 °C).
  • Wettest month: December (155 mm); driest: April (69 mm).
  • In 2025, January was Aomori's quietest month for visitors and August the busiest.

Sources

Weather normals and daylight copied from our country or prefecture page; tourism shares from the same page. See how we research.

  1. Weather: 出典:気象庁ホームページ(青森 平年値). Japan Meteorological Agency, 1991–2020 normals for the Aomori station: daily maximum and minimum temperature, precipitation, days with at least 1.0 mm of precipitation (降水量の階級日数) and hours of sunshine (日照時間). Accessed 22 September 2026. Licensed under PDL1.0. 気象庁「平年値」を加工して作成 — edited by Gallivanting Gadabout (English wording, selection and rounding).
  2. Daylight: our calculation of the time from sunrise to sunset on the 15th of each month of 2026 at the weather station's location, by the method of the NOAA Solar Calculator (NOAA Global Monitoring Laboratory, “Solar Calculation Details”, based on Jean Meeus, Astronomical Algorithms, allowing 0.833° for refraction and the size of the sun). Read it. Checked 22 September 2026. NOAA notes that calculated times can differ from what is observed.
  3. Source: 「宿泊旅行統計調査」(観光庁) (Overnight Travel Statistics Survey, Japan Tourism Agency), 2025 annual figures (final), tables 2 and 8 and reference table 1, published 6 July 2026. Survey page · workbook. Accessed 17 September 2026. Licensed under the Public Data License 1.0 (PDL1.0).
  4. Sea temperature: NOAA Optimum Interpolation Sea Surface Temperature (OISST) v2.1, 0.25° grid, monthly long-term mean 1991–2020 (file sst.mon.ltm.1991-2020.nc). Data provided by the NOAA/OAR/PSL, Boulder, Colorado, USA, from their Web site at https://psl.noaa.gov/. Huang, B., C. Liu, V. Banzon, E. Freeman, G. Graham, B. Hankins, T. Smith and H.-M. Zhang (2021), Improvements of the Daily Optimum Interpolation Sea Surface Temperature (DOISST) Version 2.1, Journal of Climate 34, 2923–2939, doi:10.1175/JCLI-D-20-0166.1. Dataset page. Accessed 24 September 2026. Public domain (NOAA PSL disclaimer). The choice of grid cell and the rounding are ours; these are not official NOAA figures, and NOAA does not endorse this site.

Modified data: the arrangement, the golden-hour and sea columns and the quietest/busiest comparison are ours, from the cited figures.