Seia climate — normals and trends
Seia (Portugal) has a warm-summer mediterranean climate (Csb) under the Köppen-Geiger classification. Its mean annual temperature is 13.0 °C and it receives 1,054 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 July (20.9 °C on average) and the coldest is January (6.0 °C). Rainfall peaks in December.
Seia averages 16 frost days, 23 hot days (≥ 30 °C) and 112 rainy days per year.
Seia has warmed by +1.3 °C between 1940 and 2025, or +0.15 °C per decade. This trend is statistically significant.
The number of frost days there went from about 25 to 7 per year over the period.
The hottest day of the period reached 39.2 °C (on 22 August 2023) and the coldest -9.6 °C (on 4 February 1963).
Data from ERA5 reanalysis (Copernicus Climate Change Service), redistributed under a CC-BY 4.0 licence. Normals are recomputed whenever the archive is updated.
Climate normals · ERA5
SeiaGuarda District
- coords
- 40.42°, -7.71°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
13.0°C
Average daily high
17.7°C
Average daily low
8.7°C
Annual rainfall
1,054mm
Sunshine / day
9.5h
Mean relative humidity
74%
Average peak wind
14.3km/h
Seasonal range
14.9°C
Frost days (< 0 °C)
16 d/yr
Hot days (≥ 30 °C)
23 d/yr
Rainy days (≥ 1 mm)
112 d/yr
Annual snowfall
5.1 cm
Average feels-like high
16.4 °C
Average feels-like low
6.7 °C
Average peak gust
36.6 km/h
Tropical nights (≥ 20 °C)
4 d/yr
Solar radiation
15.9 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+1.3 °C
since 1940
+0.2 °C per decade · r² = 0.18 · 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).
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
Hottest day
39.2 °C
22 August 2023
Coldest day
-9.6 °C
4 February 1963
Wettest day
96 mm
24 November 2006
Windiest day
47.0 km/h
30 December 1981
Strongest gust
138.6 km/h
30 December 1981
Hottest feels-like
40.0 °C
14 July 2022
Coldest feels-like
-14.2 °C
4 February 1963
Snowiest day
23.0 cm
23 February 1956
Sunniest day
14.9 h
12 June 1940
Normals computed over complete calendar years 1940–2025.
A specific year
Pick a year and see how it compares to normal — warmer, drier or more extreme than usual?
Across the whole year
Month by month
| High | vs. normal | Precipitation | vs. normal | |
|---|---|---|---|---|
| Jan | 11.7 °C | +2.1 °C | 274 mm | +140 mm |
| Feb | 13.0 °C | +1.9 °C | 56 mm | -65 mm |
| Mar | 13.4 °C | -0.4 °C | 201 mm | +90 mm |
| Apr | 17.3 °C | +1.5 °C | 150 mm | +54 mm |
| May | 20.8 °C | +1.8 °C | 67 mm | -15 mm |
| Jun | 28.1 °C | +4.6 °C | 20 mm | -21 mm |
| Jul | 29.7 °C | +2.5 °C | 6 mm | -9 mm |
| Aug | 30.9 °C | +3.6 °C | 4 mm | -12 mm |
| Sep | 24.4 °C | +0.5 °C | 33 mm | -21 mm |
| Oct | 21.5 °C | +3.0 °C | 155 mm | +37 mm |
| Nov | 13.5 °C | +0.4 °C | 264 mm | +135 mm |
| Dec | 10.5 °C | +0.4 °C | 160 mm | +23 mm |
The year's extremes
What was the weather like that day?
Your birthday, a wedding, a memorable trip: discover the actual weather for any date since 1940.
Frequently asked questions
What is the climate of Seia?
Seia has a warm-summer mediterranean climate (Köppen Csb). Over 1940-2025, the average annual temperature is 13.0 °C and it receives 1,054 mm of precipitation per year.
What is the hottest day ever recorded in Seia?
The hottest day measured in Seia between 1940 and 2025 was 22 August 2023, reaching 39.2 °C.
What is the coldest day in Seia?
The coldest day measured in Seia between 1940 and 2025 was 4 February 1963, at -9.6 °C.
Does it snow in Seia?
Yes. Seia gets on average 5.1 cm of snow per year and has around 16 frost days.
Has the climate of Seia warmed?
Yes: Seia warmed by +1.3 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Seia?
The wettest day measured in Seia between 1940 and 2025 was 24 November 2006, with 96 mm of rain in 24 hours.
What was the windiest day in Seia?
The windiest day measured in Seia between 1940 and 2025 was 30 December 1981, with winds reaching 47.0 km/h.
What is the warmest month in Seia?
The warmest month in Seia is July (20.9 °C on average); the coldest is January (6.0 °C).
How much does it rain in Seia?
Seia receives on average 1,054 mm of precipitation per year, spread over about 112 rainy days.
Is it sunny in Seia?
Seia gets on average 9.5 hours of sunshine per day, roughly 3,468 hours per year over 1940-2025.
What is the biggest single-day snowfall in Seia?
The heaviest 24-hour snowfall measured in Seia between 1940 and 2025 was 23 February 1956, with 23.0 cm.
Are there tropical nights in Seia?
Yes: Seia has on average 4 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Seia?
In Seia, between 1940 and 2025, the highest apparent temperature reached 40.0 °C on 14 July 2022, and the lowest was -14.2 °C on 4 February 1963.
Compare Seia with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Seia