Climate and average weather in Castelo Branco
In Castelo Branco, the summers are hot, dry, and clear and the winters are cool and partly cloudy.
Over the course of the year, the temperature in Castelo Branco typically varies from 5°C to 32°C, and is rarely below 1°C or above 38°C. July is the hottest month of the year, while January is the coldest.
Based on the travel score, the best times of year to visit Castelo Branco for warm-weather activities are from mid March to late June and early September to late October.
- Hottest
- Jul
- 32°
- Coldest
- Jan
- 5°
- Wettest
- Oct
- 83 mm
- Driest
- Jul
- 4 mm
- Rain / yr
- 562 mm
- 72 wet days
- Daylight
- 9.2–14.8 h
- shortest–longest
- Elevation
- 371 m
- 39.8°N
- Clearest
- Jul
- 17% cloud
Castelo Branco is city seat of Castelo Branco municipality.
Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.
Castelo Branco weather by month, at a glance
The whole year in one picture — sky, rain, humidity, temperature and travel score. Click any band to jump to its full chart.
Each stripe is one measure across the whole year, stacked so a single day reads top to bottom. The sky band runs overcast grey on top down to clear blue at the base — more blue means sunnier — followed by the rainfall curve, the humidity band, a temperature strip that tints each stretch of the year by how warm its average high is, and the travel-score line at the foot. Scan straight down any date to read that day across every measure at once; the score climbs highest around mid March to late June.
Temperature through the year
Daily average highs and lows in Castelo Branco, from 1991–2020 of climate data. The shaded bands show the range most days fall in — 10th to 90th percentile.
The hot season lasts 3.2 months, from June 11 to September 15, with daily high temperatures above 28°C. The hottest month of the year in Castelo Branco is July, with an average high of 32°C and low of 18°C.
The cool season lasts 3.6 months, from November 14 to March 4, with daily high temperatures below 16°C. The coldest month of the year in Castelo Branco is January, with an average low of 5°C and high of 13°C.
Days typically run about 11°C warmer than nights, with the widest day–night swing (around 15°C) in July.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high (°C) | 13 | 15 | 18 | 20 | 24 | 29 | 32 | 32 | 28 | 22 | 16 | 13 |
| Avg low (°C) | 5 | 5 | 8 | 9 | 12 | 15 | 18 | 18 | 16 | 12 | 8 | 6 |
| Avg high (°C) | Avg low (°C) | |
|---|---|---|
| Jan | 13 | 5 |
| Feb | 15 | 5 |
| Mar | 18 | 8 |
| Apr | 20 | 9 |
| May | 24 | 12 |
| Jun | 29 | 15 |
| Jul | 32 | 18 |
| Aug | 32 | 18 |
| Sep | 28 | 16 |
| Oct | 22 | 12 |
| Nov | 16 | 8 |
| Dec | 13 | 6 |
How hot and cold Castelo Branco really feels
The felt-temperature range through the year — heat index on the day's high (summer humidity), wind chill on the night's low (winter wind). The dashed lines are the plain thermometer; the gap is how much hotter or colder it really feels.
On the hottest afternoons, once humidity is folded in, Castelo Branco feels like about 33°C (around July 25). About 40 days a year carry some heat stress, peaking in July.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Feels-like high (°C) | 13 | 15 | 18 | 20 | 24 | 29 | 32 | 32 | 28 | 22 | 16 | 13 |
| Air high (°C) | 13 | 15 | 18 | 20 | 24 | 29 | 32 | 32 | 28 | 22 | 16 | 13 |
| Feels-like low (°C) | 2 | 3 | 6 | 8 | 12 | 15 | 18 | 18 | 16 | 12 | 6 | 3 |
| Air low (°C) | 5 | 5 | 8 | 9 | 12 | 15 | 18 | 18 | 16 | 12 | 8 | 6 |
| Feels-like high (°C) | Air high (°C) | Feels-like low (°C) | Air low (°C) | |
|---|---|---|---|---|
| Jan | 13 | 13 | 2 | 5 |
| Feb | 15 | 15 | 3 | 5 |
| Mar | 18 | 18 | 6 | 8 |
| Apr | 20 | 20 | 8 | 9 |
| May | 24 | 24 | 12 | 12 |
| Jun | 29 | 29 | 15 | 15 |
| Jul | 32 | 32 | 18 | 18 |
| Aug | 32 | 32 | 18 | 18 |
| Sep | 28 | 28 | 16 | 16 |
| Oct | 22 | 22 | 12 | 12 |
| Nov | 16 | 16 | 6 | 8 |
| Dec | 13 | 13 | 3 | 6 |
Average hourly temperature in Castelo Branco
A compact picture of the whole year, hour by hour: each column is a day, each row an hour, and the color is the modeled average temperature. Darker overlays mark night, lighter ones the civil-twilight hours around sunrise and sunset.
Read left to right for the day of the year and top to bottom for the hour of the day; the color is the modeled temperature, cool blues through to hot reds on the same scale as the other charts. A vertical slice is a single day's swing — coolest just before dawn, warmest in the mid-afternoon — while a horizontal slice follows one hour across the seasons. The darker overlay marks night and the lighter one the twilight around sunrise and sunset. Colors run warmest on July afternoons, near 32°C, and coldest before dawn in January, near 5°C.
Castelo Branco weather by month
Every month at a glance. Click a month for its detailed page.
| Month | High / Low (°C) | Rainfall (mm) | Wet days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|
| Jan | 13° / 5° | 62 | 8.2 | 9.5 | 3.7 |
| Feb | 15° / 5° | 49 | 6.4 | 10.4 | 4.8 |
| Mar | 18° / 8° | 58 | 7.4 | 11.7 | 6.2 |
| Apr | 20° / 9° | 53 | 8.1 | 13 | 6.6 |
| May | 24° / 12° | 51 | 7 | 14.2 | 7.5 |
| Jun | 29° / 15° | 10 | 2.5 | 14.8 | 7.0 |
| Jul | 32° / 18° | 4 | 1.3 | 14.5 | 5.1 |
| Aug | 32° / 18° | 6 | 1.4 | 13.6 | 5.2 |
| Sep | 28° / 16° | 34 | 4.6 | 12.3 | 7.1 |
| Oct | 22° / 12° | 83 | 8.9 | 10.9 | 6.9 |
| Nov | 16° / 8° | 77 | 8.3 | 9.8 | 5.4 |
| Dec | 13° / 6° | 75 | 8.3 | 9.2 | 3.9 |
Chance of rain
How likely it is to rain on a typical day, and how that shifts across the wetter and drier seasons.
Castelo Branco gets about 562 mm of precipitation a year. On a typical day the chance of rain is some rain, but that rises and falls sharply with the seasons.
The wetter season lasts 7.8 months, from around Sep 27 to May 22, peaking in October at about 33% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Aug 5.
October is the wettest month by volume, with 83 mm over about 9 wet days; July is the driest, with 4 mm.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rain on a day (%) | 27 | 23 | 24 | 27 | 22 | 9 | 4 | 5 | 15 | 28 | 28 | 27 |
| Rain days | 8 | 6 | 7 | 8 | 7 | 3 | 1 | 1 | 5 | 9 | 8 | 8 |
| Rain on a day (%) | Rain days | |
|---|---|---|
| Jan | 27 | 8 |
| Feb | 23 | 6 |
| Mar | 24 | 7 |
| Apr | 27 | 8 |
| May | 22 | 7 |
| Jun | 9 | 3 |
| Jul | 4 | 1 |
| Aug | 5 | 1 |
| Sep | 15 | 5 |
| Oct | 28 | 9 |
| Nov | 28 | 8 |
| Dec | 27 | 8 |
Monthly rainfall
Over a full year, Castelo Branco collects about 562 mm of rain across 72 wet days — roughly 47 mm in an average month.
It doesn’t fall evenly. October is the wettest month with 83 mm, while July is the driest at just 4 mm. The three wettest months alone bring about 42% of the year’s total.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rainfall (mm) | 62 | 49 | 58 | 53 | 51 | 10 | 4 | 6 | 34 | 83 | 77 | 75 |
| Rain days | 8 | 6 | 7 | 8 | 7 | 3 | 1 | 1 | 5 | 9 | 8 | 8 |
| Rainfall (mm) | Rain days | |
|---|---|---|
| Jan | 62 | 8 |
| Feb | 49 | 6 |
| Mar | 58 | 7 |
| Apr | 53 | 8 |
| May | 51 | 7 |
| Jun | 10 | 3 |
| Jul | 4 | 1 |
| Aug | 6 | 1 |
| Sep | 34 | 5 |
| Oct | 83 | 9 |
| Nov | 77 | 8 |
| Dec | 75 | 8 |
Clouds and sunshine
How often the daytime sky is clear, partly cloudy or overcast.
In Castelo Branco, the average share of the sky covered by clouds shows significant seasonal variation over the course of the year.
The clearer part of the year begins around May 24 and lasts for 4.4 months, ending around October 4. The clearest month is July, when the sky is clear, mostly clear, or partly cloudy 90% of the time on average.
The cloudier part of the year begins around October 5 and lasts for 7.6 months, ending around May 23. The cloudiest month is December, when it is overcast or mostly cloudy 52% of the time.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Clearer (%) | 51 | 53 | 53 | 52 | 58 | 75 | 90 | 88 | 74 | 53 | 50 | 48 |
| Cloudier (%) | 49 | 47 | 47 | 48 | 42 | 25 | 10 | 12 | 26 | 47 | 50 | 52 |
| Clearer (%) | Cloudier (%) | |
|---|---|---|
| Jan | 51 | 49 |
| Feb | 53 | 47 |
| Mar | 53 | 47 |
| Apr | 52 | 48 |
| May | 58 | 42 |
| Jun | 75 | 25 |
| Jul | 90 | 10 |
| Aug | 88 | 12 |
| Sep | 74 | 26 |
| Oct | 53 | 47 |
| Nov | 50 | 50 |
| Dec | 48 | 52 |
Daylight, sunrise and sunset
Hours of daylight through the year, with sunrise and sunset times.
The gold band is daylight — sunrise runs along its lower edge, sunset along the upper — so it widens toward summer and pinches toward winter, with night the dark area above and below. The longest day, around June 11, brings about 14 h 48 min of light; the shortest, around January 1, only 9 h 12 min — a swing of roughly 5 h 36 min.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Daylight (h) | 9.5 | 10.4 | 11.7 | 13.0 | 14.2 | 14.8 | 14.5 | 13.6 | 12.3 | 10.9 | 9.8 | 9.2 |
| Sunrise (AM) | 7:55 | 7:31 | 6:49 | 5:59 | 5:21 | 5:06 | 5:19 | 5:47 | 6:17 | 6:47 | 7:22 | 7:50 |
| Sunset (PM) | 5:23 | 5:58 | 6:30 | 7:02 | 7:32 | 7:54 | 7:52 | 7:22 | 6:32 | 5:43 | 5:08 | 5:02 |
| Daylight (h) | Sunrise (AM) | Sunset (PM) | |
|---|---|---|---|
| Jan | 9.5 | 7:55 | 5:23 |
| Feb | 10.4 | 7:31 | 5:58 |
| Mar | 11.7 | 6:49 | 6:30 |
| Apr | 13.0 | 5:59 | 7:02 |
| May | 14.2 | 5:21 | 7:32 |
| Jun | 14.8 | 5:06 | 7:54 |
| Jul | 14.5 | 5:19 | 7:52 |
| Aug | 13.6 | 5:47 | 7:22 |
| Sep | 12.3 | 6:17 | 6:32 |
| Oct | 10.9 | 6:47 | 5:43 |
| Nov | 9.8 | 7:22 | 5:08 |
| Dec | 9.2 | 7:50 | 5:02 |
Sunny days
How many genuinely sunny days each month brings — days the sky stays clear or mostly clear — banded into plain-language zones.
Castelo Branco averages about 15 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 9 and 26 days.
The sunnier stretch runs 4.0 months, from around Jun 4 to Oct 3. The sunniest month is July, with roughly 25 sunny days (brilliant).
The greyest month is October, down near 12 sunny days — about 53% fewer than the July peak.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sunny days | 12 | 11 | 12 | 11 | 12 | 18 | 25 | 24 | 18 | 12 | 11 | 11 |
| Sky | Mixed | Mixed | Mixed | Mixed | Mixed | Bright | Brilliant | Brilliant | Bright | Mixed | Mixed | Mixed |
| Sunny days | Sky | |
|---|---|---|
| Jan | 12 | Mixed |
| Feb | 11 | Mixed |
| Mar | 12 | Mixed |
| Apr | 11 | Mixed |
| May | 12 | Mixed |
| Jun | 18 | Bright |
| Jul | 25 | Brilliant |
| Aug | 24 | Brilliant |
| Sep | 18 | Bright |
| Oct | 12 | Mixed |
| Nov | 11 | Mixed |
| Dec | 11 | Mixed |
Humidity comfort
Share of days at each humidity comfort level, based on the dew point — the measure that tracks how muggy it actually feels.
Humidity comfort is graded by the dew point — the temperature at which the air would be fully saturated — because it tracks how muggy it actually feels far better than relative humidity does. A low dew point feels dry and crisp; a high one feels sticky and oppressive no matter the reading on a humidity gauge.
In Castelo Branco, the air stays dry or comfortable essentially all year. Even in August, the muggiest month, it feels humid or worse only about 8% of the time — humidity is not something you need to plan around here.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Dry (%) | 99 | 99 | 99 | 97 | 85 | 68 | 53 | 51 | 61 | 70 | 91 | 97 |
| Comfortable (%) | 1 | 1 | 1 | 3 | 14 | 28 | 41 | 41 | 31 | 24 | 8 | 3 |
| Humid (%) | 0 | 0 | 0 | 0 | 1 | 3 | 6 | 8 | 8 | 5 | 1 | 0 |
| Dry (%) | Comfortable (%) | Humid (%) | |
|---|---|---|---|
| Jan | 99 | 1 | 0 |
| Feb | 99 | 1 | 0 |
| Mar | 99 | 1 | 0 |
| Apr | 97 | 3 | 0 |
| May | 85 | 14 | 1 |
| Jun | 68 | 28 | 3 |
| Jul | 53 | 41 | 6 |
| Aug | 51 | 41 | 8 |
| Sep | 61 | 31 | 8 |
| Oct | 70 | 24 | 5 |
| Nov | 91 | 8 | 1 |
| Dec | 97 | 3 | 0 |
Wind
Average wind speed through the year, banded into plain-language speed zones so a number reads as 'breezy' or 'calm' without knowing the scale.
This is the average sustained wind speed at the standard 10 metres above open ground — the steady flow a weather station reports, not the sharper gusts that come and go, which can run half again as fast. It's the number that says whether a place is generally breezy or calm.
Wind in Castelo Branco is steady company: average speeds sit near 10 km/h — calm — in every month of the year, with no meaningful windy or calm season.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Wind speed (km/h) | 10 | 10 | 10 | 10 | 10 | 9 | 9 | 9 | 9 | 9 | 10 | 10 |
| Feels | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm |
| Wind speed (km/h) | Feels | |
|---|---|---|
| Jan | 10 | calm |
| Feb | 10 | calm |
| Mar | 10 | calm |
| Apr | 10 | calm |
| May | 10 | calm |
| Jun | 9 | calm |
| Jul | 9 | calm |
| Aug | 9 | calm |
| Sep | 9 | calm |
| Oct | 9 | calm |
| Nov | 10 | calm |
| Dec | 10 | calm |
Best time to visit Castelo Branco
To characterize how pleasant the weather is in Castelo Branco throughout the year, we compute two travel scores — one for general sightseeing, one for beach and pool weather.
Around late March, Castelo Branco is still near the start of its best-weather window — great conditions with the peak-season crowds not yet at full swing.
Inferred from the travel-score curve; month-by-month visitor numbers are a planned addition.
The travel score favors clear, rainless days with daytime highs between 18°C and 28°C. Based on this score, the best times of year to visit Castelo Branco for general outdoor tourist activities run from mid March to late June and again from early September to late October, with a peak score in the last week of May.
The travel score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Travel score (0–10) | 3.7 | 4.8 | 6.2 | 6.6 | 7.4 | 6.9 | 5.1 | 5.2 | 7.0 | 6.9 | 5.4 | 3.9 |
| Rating | fair | fair | good | good | good | good | fair | fair | good | good | fair | fair |
| Travel score (0–10) | Rating | |
|---|---|---|
| Jan | 3.7 | fair |
| Feb | 4.8 | fair |
| Mar | 6.2 | good |
| Apr | 6.6 | good |
| May | 7.4 | good |
| Jun | 6.9 | good |
| Jul | 5.1 | fair |
| Aug | 5.2 | fair |
| Sep | 7.0 | good |
| Oct | 6.9 | good |
| Nov | 5.4 | fair |
| Dec | 3.9 | fair |
The beach/pool score favors clear, rainless days with daytime highs between 24°C and 34°C. Based on this score, the best time of year to visit Castelo Branco for hot-weather activities is from late May to early October, with a peak score in the last week of June.
The beach/pool score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).
What to pack for Castelo Branco, by month
Month by month, what's worth putting in the bag — from the temperature range, rain chance, sun and wind. Tap a month for a quick packing note.
For a warm-season trip around July (highs near 32°C), the essentials are light clothes and sun protection. In the cold season around January (highs near 13°C), pack a warm layer and rain gear.
In July, Castelo Branco sees daytime highs around 32°C and nights near 18°C. Pack light clothes and sun protection.
UV index (midday) in Castelo Branco by month
Clear-sky midday UV index through the year, shaded by the WHO exposure levels — how much sun protection each month calls for.
Under clear skies, the midday UV index in Castelo Branco peaks around July 17 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 18 at about 2 (low).
The index reaches 3 or more — the level where the WHO recommends sun protection — in 8 months of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 2 | 3 | 6 | 7 | 7 | 9 | 9 | 9 | 6 | 5 | 2 | 2 |
| Level | Low | Moderate | High | High | High | Very high | Very high | Very high | High | Moderate | Moderate | Low |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 2 | Low |
| Feb | 3 | Moderate |
| Mar | 6 | High |
| Apr | 7 | High |
| May | 7 | High |
| Jun | 9 | Very high |
| Jul | 9 | Very high |
| Aug | 9 | Very high |
| Sep | 6 | High |
| Oct | 5 | Moderate |
| Nov | 2 | Moderate |
| Dec | 2 | Low |
Average hourly UV index in Castelo Branco
Modeled clear-sky UV for every hour of every day — when in the day sun protection actually matters.
The whole year hour by hour: each column is a day, each row an hour, and the color is the modeled clear-sky UV index — the midday peak scaled down as the sun sits lower in the sky. Darker overlays mark night, lighter ones the civil-twilight hours around sunrise and sunset.
UV falls off far faster than brightness as the sun drops, so even in July the burn window is concentrated in the middle of the day: about 8.5 hours a day reach index 3 (protection recommended), and 5.5 hours reach 6 or more. Mornings and late afternoons stay comparatively gentle year round.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV ≥ 3 (h/day) | 0 | 0.5 | 5.5 | 7 | 7.5 | 8.5 | 8.5 | 8 | 6 | 4.5 | 0 | 0 |
| UV ≥ 6 (h/day) | 0 | 0 | 0 | 3 | 3.5 | 5.5 | 5.5 | 5 | 0 | 0 | 0 | 0 |
| UV ≥ 3 (h/day) | UV ≥ 6 (h/day) | |
|---|---|---|
| Jan | 0 | 0 |
| Feb | 0.5 | 0 |
| Mar | 5.5 | 0 |
| Apr | 7 | 3 |
| May | 7.5 | 3.5 |
| Jun | 8.5 | 5.5 |
| Jul | 8.5 | 5.5 |
| Aug | 8 | 5 |
| Sep | 6 | 0 |
| Oct | 4.5 | 0 |
| Nov | 0 | 0 |
| Dec | 0 | 0 |
Air quality in Castelo Branco by month
Average fine-particle pollution (PM2.5) through the year — so you can see which months the air is worst, not just the yearly average.
Air quality in Castelo Branco is worst in August — around 21 µg/m³ PM2.5 (moderate), about 3.3× the cleanest month (November, 6 µg/m³).
Modeled monthly averages (CAMS reanalysis, 2015–2024).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 (µg/m³) | 8 | 10 | 12 | 10 | 8 | 9 | 12 | 21 | 10 | 14 | 6 | 7 |
| Level | Good | Good | Moderate | Good | Good | Good | Good | Moderate | Good | Moderate | Good | Good |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 8 | Good |
| Feb | 10 | Good |
| Mar | 12 | Moderate |
| Apr | 10 | Good |
| May | 8 | Good |
| Jun | 9 | Good |
| Jul | 12 | Good |
| Aug | 21 | Moderate |
| Sep | 10 | Good |
| Oct | 14 | Moderate |
| Nov | 6 | Good |
| Dec | 7 | Good |
Growing season
Castelo Branco is mild enough that a frost-free day stays more likely than not even in midwinter.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Frost-free chance (%) | 92 | 96 | 99 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 99 | 95 |
| Frost nights | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Frost-free chance (%) | Frost nights | |
|---|---|---|
| Jan | 92 | 0 |
| Feb | 96 | 0 |
| Mar | 99 | 0 |
| Apr | 100 | 0 |
| May | 100 | 0 |
| Jun | 100 | 0 |
| Jul | 100 | 0 |
| Aug | 100 | 0 |
| Sep | 100 | 0 |
| Oct | 100 | 0 |
| Nov | 99 | 0 |
| Dec | 95 | 0 |
Growing degree days
Growing degree days tally heat above 10°C: each day adds however many degrees its average temperature runs over that threshold, and cold days add nothing. Castelo Branco banks about 2,387 degree days a year, and the running total — which growers use to time plantings and predict maturity — climbs fastest around August.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Growing degree days (°C·days) | 0 | 5 | 81 | 134 | 244 | 361 | 462 | 462 | 352 | 221 | 65 | 0 |
| Growing degree days (°C·days) | |
|---|---|
| Jan | 0 |
| Feb | 5 |
| Mar | 81 |
| Apr | 134 |
| May | 244 |
| Jun | 361 |
| Jul | 462 |
| Aug | 462 |
| Sep | 352 |
| Oct | 221 |
| Nov | 65 |
| Dec | 0 |
Solar energy
Average daily shortwave solar energy reaching the ground, banded into brightness zones so the number means something at a glance.
Solar energy is how much sunlight actually reaches the ground each day, measured in kilowatt-hours per square metre (kWh/m²) — the combined effect of how long the sun is up, how high it climbs, and how much cloud gets in the way. It's the raw fuel a solar panel has to work with: for scale, 1 kWh/m² a day is dim and wintry, while 7+ is desert-bright.
Castelo Branco receives about 4.7 kWh/m² a day of solar energy on average — bright — with a clear seasonal swing between 1.8 and 7.8 kWh/m².
The brighter stretch of the year lasts 6.0 months, from around Mar 24 to Sep 23. The brightest month is July, averaging about 7.7 kWh/m² (intense).
The dimmest month is December, down near 1.9 kWh/m² — roughly 76% less than the July peak.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Solar energy (kWh/m²) | 2.1 | 3.1 | 4.4 | 5.5 | 6.5 | 7.4 | 7.7 | 6.8 | 5.2 | 3.4 | 2.3 | 1.8 |
| Level | Moderate | Moderate | Bright | Bright | Intense | Intense | Intense | Intense | Bright | Moderate | Moderate | Dim |
| Solar energy (kWh/m²) | Level | |
|---|---|---|
| Jan | 2.1 | Moderate |
| Feb | 3.1 | Moderate |
| Mar | 4.4 | Bright |
| Apr | 5.5 | Bright |
| May | 6.5 | Intense |
| Jun | 7.4 | Intense |
| Jul | 7.7 | Intense |
| Aug | 6.8 | Intense |
| Sep | 5.2 | Bright |
| Oct | 3.4 | Moderate |
| Nov | 2.3 | Moderate |
| Dec | 1.8 | Dim |
Where is Castelo Branco?
Castelo Branco sits at 39.8°N, 7.5°W, 371 m above sea level, in Portugal. The nearest listed city is Covilhã, 51 km away.
Topography around Castelo Branco
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Castelo Branco.
Within 3 km, the terrain around Castelo Branco has only modest variations in elevation — a maximum elevation change of 184 m around an average of 362 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 363 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,974 m.
The land around Castelo Branco is covered by grassland (48%), trees (27%) and artificial surfaces (21%) within 3 km, grassland (49%) and trees (39%) within 16 km, and grassland (50%) and trees (43%) within 80 km.
Portugal travel facts
- Travel advisory
- Level 1
- Exercise Normal Precautions
- Power plugs
- Type C / E / F
- 230 V · 50 Hz
- Prices
- ≈ 60% of US
- price level, 2025
- GDP per capita
- $32,082
- 2025
- Happiness
- 6.0 / 10
- World Happiness, 2025
- Safe drinking water
- 95%
- of population, 2024
- Homicide rate
- 0.7
- per 100k, 2022
- Road deaths
- 8.2
- per 100k/yr, 2019
- Income group
- High
- World Bank
- English
- Very high
- EF EPI 612
- Religion
Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.
Data sources
Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Castelo Branco (39.8236°, -7.491°, elevation 371 m), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).