WeatherJourney.com

Hailun weather by month — averages, rainfall & climate trends

Average temperatures and rainfall by month, a climate graph, today's conditions versus the long-term average, and how the climate has shifted since 1940 — all on one page for Hailun, China.

Right now

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

Right now

22.4°

25°feels like
93%humidity
21°dew point
12 km/hfrom S
sunrise04:04sunset19:12day length15h 08m
TueShowers28°22°
WedOvercast28°21°
ThuOvercast28°20°
FriLight rain28°20°
SatOvercast22°19°
SunOvercast26°19°
MonOvercast29°21°

On this date — July 27

Today (forecast)
28° / 22°
Average for July 27
26° / 18°

About average

  • Record high: 30.9° · 1963
  • Record low: 10.1° · 1954
  • One year ago: 28.3°

Every July 27 in history — coldest to hottest

Daily highsDaily lows

Dots show daily highs (top) and lows (bottom) for each July 27 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 Hailun is sampled from the ECMWF ERA5 reanalysis at 47.45°N, 126.92°E, with daily records since 1940.

Coordinates
47.45°N, 126.92°E
Time zone
Asia/Shanghai
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: +1.1°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 — 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 — what a typical year looks like, from the full record.

Climate overview

Seasons run to extremes in Hailun: monthly means span 44.1°C between the coldest month and the warmest. July brings the year's peak warmth: daily means of 21.8°C, with afternoons typically reaching 26.1°C. In January, daily means drop to roughly -22.3°C, with nights dipping to -28.6°C. Around 180 days a year dip below freezing.

Rainfall is strongly seasonal: the bulk of the year's rain falls between May and September. The yearly total for Hailun comes to about 729 mm; monthly amounts range from 7 mm in January up to 172 mm in July.

Over the full record (since 1940), the annual mean temperature in Hailun has risen by 1.5°C between its first decade and its last. No period since 1940 has been warmer than the most recent decade.

Climate graph (climograph)

July is the warmest month, January the coolest — a yearly swing of 44°C. Wettest month: July (~172 mm). Whole year averages ~729 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).

Monthly wind

Average daily peak wind at 10 m, by month.

Monthly solar energy

Average daily incoming solar energy in megajoules per square metre — a measured proxy for how sunny the month is.

Hailun 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. Record high/low are the most extreme values in the ERA5 dataset (modelled since 1940), so they can differ from official weather-station readings.

MonthAvg highAvg lowRainDaylightRecord highRecord low
January-16.3°-28.6°7 mm8.7 h-1.0° (2013)-44.0° (2001)
February-10.6°-23.9°8 mm10.0 h7.9° (2019)-41.6° (1952)
March-0.7°-12.5°18 mm11.6 h18.9° (2023)-31.4° (2018)
April10.6°-0.3°41 mm13.4 h27.8° (2015)-16.4° (1971)
May18.5°7.2°68 mm14.9 h32.6° (1998)-4.3° (1961)
June24.0°14.2°109 mm15.7 h36.0° (2001)3.1° (1964)
July26.1°17.7°172 mm15.4 h35.7° (1982)8.1° (1959)
August24.3°15.5°146 mm14.1 h34.1° (1982)3.8° (1976)
September18.5°8.3°90 mm12.3 h31.0° (2010)-5.1° (1967)
October9.3°-0.7°41 mm10.6 h25.7° (2025)-19.7° (1982)
November-3.6°-13.3°18 mm9.0 h14.1° (1994)-33.7° (1981)
December-14.2°-25.0°11 mm8.3 h5.8° (2018)-41.4° (1952)

How it has changed

Year-by-year signals from 1940 to today.

Climate stripes

Annual mean shifted from 1940–1949 to 2016–2025 by +1.5°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: +0.25°C per decade.

One point per year — 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

Mar–May is warming fastest: +0.38°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: 2.8 early in the record → 7.7 recently. Frost days: 184 → 179.

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

All-time high in 2001, all-time low in 2001: 36.0°C / -44.0°C.

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

Annual rainfall

~729 mm/year on average. Last decade ran +0% vs that average. Long-term trend: 9 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 — ~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).

Hailun — Frequently asked questions

Which is the warmest month in Hailun?
On long-term average, the warmest month in Hailun is July (mean about 21.8°C) and the coolest is January (about -22.3°C).
How does today's temperature in Hailun compare to the historical average?
On 2026-07-27, Hailun is forecast to reach a high of 27.9°C and a low of 22.3°C. The long-term average for this date (the full record since 1940) is a high of 26.3°C and a low of 18.0°C — today's high is 1.6°C warmer than that average.
How much has Hailun warmed since 1940?
Comparing the first decade of the record (1940–1949) with the most recent (2016–2025), the annual mean temperature in Hailun is about 1.5°C warmer.
How much does it rain in Hailun?
Hailun receives about 729 mm of precipitation per year on long-term average, with July typically the wettest month.
What is the average temperature in Hailun?
Over the full record (since 1940), the annual mean temperature in Hailun is about 1.9°C. The warmest month is July and the coolest is January.
What are the average temperatures in Hailun by month?
Average daily highs and lows for each month in Hailun (°C, full record since 1940): January -16°/-29°, February -11°/-24°, March -1°/-12°, April 11°/0°, May 19°/7°, June 24°/14°, July 26°/18°, August 24°/16°, September 19°/8°, October 9°/-1°, November -4°/-13°, December -14°/-25°.
How many days a year does it rain in Hailun?
On long-term average, Hailun has about 98 days a year with measurable rain, totalling roughly 729 mm.

Weather in nearby cities