Dellys climate — normals and trends
Dellys has a hot-summer mediterranean climate, averaging 18.0 °C annually with 829 mm of rain per year.
Climate normals · ERA5
DellysBoumerdes Province
- coords
- 36.92°, 3.91°
- period
- 1940–2025 · 86 yrs
The normals for this period
The average of every indicator across the whole window: temperature, water, sky, wind and notable days.
Mean daily temperature
18.0°C
Average daily high
19.1°C
Average daily low
17.0°C
Annual rainfall
829mm
Sunshine / day
10.7h
Mean relative humidity
79%
Average peak wind
27.2km/h
Seasonal range
11.8°C
Frost days (< 0 °C)
0 d/yr
Hot days (≥ 30 °C)
1 d/yr
Rainy days (≥ 1 mm)
93 d/yr
Annual snowfall
0.2 cm
Average feels-like high
19.0 °C
Average feels-like low
15.4 °C
Average peak gust
37.5 km/h
Tropical nights (≥ 20 °C)
118 d/yr
Solar radiation
17.6 MJ/m²
Has the climate changed?
What the yearly averages say about warming here, and whether the slope is statistically solid.
+1.2 °C
since 1940
+0.1 °C per decade · r² = 0.47 · p = < 0.001
Trend fitted by linear regression (ordinary least squares) on annual means. A trend is shown only when it is statistically significant (p < 0.05).
Climate month by month
How an average year unfolds: when it rains, when it turns hot, when the sun is out.
A climograph overlays rainfall (bars) and temperature (line): the standard reading in climatology, where you can see at a glance whether the warm season is also the dry one.
Records for the period
The most extreme days ever measured here, then the year-by-year detail.
Hottest day
36.2 °C
18 July 2023
Coldest day
2.3 °C
5 February 2012
Wettest day
106 mm
5 October 1957
Windiest day
77.4 km/h
10 January 1987
Strongest gust
122.4 km/h
14 January 1987
Hottest feels-like
38.8 °C
23 July 2023
Coldest feels-like
-4.9 °C
26 January 2005
Snowiest day
8.3 cm
26 January 2005
Sunniest day
14.0 h
15 June 2025
Normals computed over complete calendar years 1940–2025.
A specific year
Pick a year and compare it with the normal: warmer, drier, more extreme?
Across the whole year
Month by month
| High | vs. normal | Precipitation | vs. normal | |
|---|---|---|---|---|
| Jan | 15.9 °C | +1.7 °C | 191 mm | +58 mm |
| Feb | 15.3 °C | +1.2 °C | 71 mm | -34 mm |
| Mar | 16.6 °C | +1.6 °C | 60 mm | -22 mm |
| Apr | 18.0 °C | +1.7 °C | 61 mm | -4 mm |
| May | 19.9 °C | +1.3 °C | 36 mm | -3 mm |
| Jun | 24.2 °C | +2.6 °C | 0 mm | -10 mm |
| Jul | 26.0 °C | +1.6 °C | 3 mm | +1 mm |
| Aug | 26.8 °C | +1.3 °C | 0 mm | -5 mm |
| Sep | 25.8 °C | +1.6 °C | 41 mm | +7 mm |
| Oct | 22.9 °C | +1.4 °C | 24 mm | -58 mm |
| Nov | 19.2 °C | +1.2 °C | 119 mm | -3 mm |
| Dec | 16.1 °C | +0.8 °C | 116 mm | -36 mm |
The year's extremes
What was the weather like that day?
The weather actually measured on a given date, anywhere in the covered window.
Climate at a glance
What these normals say about the place, in a few sentences, and the notions needed to read them.
Dellys (Algeria) has a hot-summer mediterranean climate (Csa) under the Köppen-Geiger classification. Its mean annual temperature is 18.0 °C and it receives 829 mm of precipitation per year.
These figures are normals computed over 86 complete calendar years, from 1940 to 2025, using ERA5 reanalysis data from the Copernicus programme.
The warmest month is August (24.7 °C on average) and the coldest is February (12.9 °C). Rainfall peaks in December.
Dellys averages 0 frost days, 1 hot days (≥ 30 °C) and 93 rainy days per year.
Dellys has warmed by +1.2 °C between 1940 and 2025, or +0.14 °C per decade. This trend is statistically significant.
The hottest day of the period reached 36.2 °C (on 18 July 2023) and the coldest 2.3 °C (on 5 February 2012).
Data from ERA5 reanalysis (Copernicus Climate Change Service), redistributed under a CC-BY 4.0 licence. Normals are recomputed whenever the archive is updated.
Compare Dellys with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Dellys
Other cities — Algeria
Frequently asked questions
What is the climate of Dellys?
Dellys has a hot-summer mediterranean climate (Köppen Csa). Over 1940-2025, the average annual temperature is 18.0 °C and it receives 829 mm of precipitation per year.
What is the hottest day ever recorded in Dellys?
The hottest day measured in Dellys between 1940 and 2025 was 18 July 2023, reaching 36.2 °C.
What is the coldest day in Dellys?
The coldest day measured in Dellys between 1940 and 2025 was 5 February 2012, at 2.3 °C.
Does it snow in Dellys?
Almost never: Dellys sees virtually no snow, with about 0 frost days per year.
Has the climate of Dellys warmed?
Yes: Dellys warmed by +1.2 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Dellys?
The wettest day measured in Dellys between 1940 and 2025 was 5 October 1957, with 106 mm of rain in 24 hours.
What was the windiest day in Dellys?
The windiest day measured in Dellys between 1940 and 2025 was 10 January 1987, with winds reaching 77.4 km/h.
What is the warmest month in Dellys?
The warmest month in Dellys is August (24.7 °C on average); the coldest is February (12.9 °C).
How much does it rain in Dellys?
Dellys receives on average 829 mm of precipitation per year, spread over about 93 rainy days.
Is it sunny in Dellys?
Dellys gets on average 10.7 hours of sunshine per day, roughly 3,905 hours per year over 1940-2025.
What is the biggest single-day snowfall in Dellys?
The heaviest 24-hour snowfall measured in Dellys between 1940 and 2025 was 26 January 2005, with 8.3 cm.
Are there tropical nights in Dellys?
Yes: Dellys has on average 118 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Dellys?
In Dellys, between 1940 and 2025, the highest apparent temperature reached 38.8 °C on 23 July 2023, and the lowest was -4.9 °C on 26 January 2005.
These forecasts and records come from our own weather API. Developer documentation →