Climate and average weather in Umm Hājar
In Umm Hājar, the summers are sweltering, dry, and mostly clear and the winters are hot and mostly cloudy.
Over the course of the year, the temperature in Umm Hājar typically varies from 17°C to 41°C, and is rarely below 13°C or above 43°C. April is the hottest month of the year, while August is the coldest.
Based on the travel score, the best times of year to visit Umm Hājar for warm-weather activities are from early January to late January and mid December to late December.
- Hottest
- Apr
- 41°
- Coldest
- Aug
- 23°
- Wettest
- Aug
- 217 mm
- Driest
- Feb
- 0 mm
- Rain / yr
- 444 mm
- 66 wet days
- Daylight
- 11.2–12.8 h
- shortest–longest
- Elevation
- 397 m
- 13.3°N
- Clearest
- Nov
- 24% cloud
Umm Hājar is place in Batha, Chad.
Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.
Umm Hājar 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 early January to late January.
Temperature through the year
Daily average highs and lows in Umm Hājar, from 1991–2020 of climate data. The shaded bands show the range most days fall in — 10th to 90th percentile.
The hot season lasts 3.3 months, from March 12 to June 18, with daily high temperatures above 39°C. The hottest month of the year in Umm Hājar is April, with an average high of 41°C and low of 26°C.
The cool season lasts 1.6 months, from July 24 to September 10, with daily high temperatures below 33°C. The coldest month of the year in Umm Hājar is August, with an average low of 23°C and high of 32°C.
Days typically run about 13°C warmer than nights, with the widest day–night swing (around 17°C) in February.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high (°C) | 33 | 36 | 39 | 41 | 41 | 39 | 35 | 32 | 34 | 38 | 37 | 34 |
| Avg low (°C) | 17 | 20 | 23 | 26 | 28 | 27 | 25 | 23 | 24 | 24 | 22 | 18 |
| Avg high (°C) | Avg low (°C) | |
|---|---|---|
| Jan | 33 | 17 |
| Feb | 36 | 20 |
| Mar | 39 | 23 |
| Apr | 41 | 26 |
| May | 41 | 28 |
| Jun | 39 | 27 |
| Jul | 35 | 25 |
| Aug | 32 | 23 |
| Sep | 34 | 24 |
| Oct | 38 | 24 |
| Nov | 37 | 22 |
| Dec | 34 | 18 |
How hot and cold Umm Hājar 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, Umm Hājar feels like about 41°C (around April 19). Nearly every day a year carries some heat stress, and 131 of them tip into dangerous heat (feels-like above 39°C), peaking in April.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Feels-like high (°C) | 33 | 36 | 39 | 41 | 41 | 40 | 38 | 36 | 38 | 38 | 37 | 34 |
| Air high (°C) | 33 | 36 | 39 | 41 | 41 | 39 | 35 | 32 | 34 | 38 | 37 | 34 |
| Feels-like low (°C) | 17 | 20 | 23 | 26 | 28 | 27 | 25 | 23 | 24 | 24 | 22 | 18 |
| Air low (°C) | 17 | 20 | 23 | 26 | 28 | 27 | 25 | 23 | 24 | 24 | 22 | 18 |
| Feels-like high (°C) | Air high (°C) | Feels-like low (°C) | Air low (°C) | |
|---|---|---|---|---|
| Jan | 33 | 33 | 17 | 17 |
| Feb | 36 | 36 | 20 | 20 |
| Mar | 39 | 39 | 23 | 23 |
| Apr | 41 | 41 | 26 | 26 |
| May | 41 | 41 | 28 | 28 |
| Jun | 40 | 39 | 27 | 27 |
| Jul | 38 | 35 | 25 | 25 |
| Aug | 36 | 32 | 23 | 23 |
| Sep | 38 | 34 | 24 | 24 |
| Oct | 38 | 38 | 24 | 24 |
| Nov | 37 | 37 | 22 | 22 |
| Dec | 34 | 34 | 18 | 18 |
Average hourly temperature in Umm Hājar
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 April afternoons, near 41°C, and coldest before dawn in August, near 23°C.
Umm Hājar 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 | 33° / 17° | 0 | 0 | 11.3 | 4.4 |
| Feb | 36° / 20° | 0 | 0 | 11.6 | 2.6 |
| Mar | 39° / 23° | 0 | 0 | 11.9 | 0.5 |
| Apr | 41° / 26° | 2 | 1 | 12.3 | 0.0 |
| May | 41° / 28° | 10 | 3.1 | 12.6 | 0.0 |
| Jun | 39° / 27° | 24 | 7 | 12.8 | 0.5 |
| Jul | 35° / 25° | 117 | 18.2 | 12.7 | 2.0 |
| Aug | 32° / 23° | 217 | 23.6 | 12.4 | 2.8 |
| Sep | 34° / 24° | 67 | 10.9 | 12.1 | 2.7 |
| Oct | 38° / 24° | 8 | 2.3 | 11.7 | 1.4 |
| Nov | 37° / 22° | 0 | 0 | 11.4 | 2.2 |
| Dec | 34° / 18° | 0 | 0 | 11.2 | 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.
Umm Hājar gets about 444 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 3.6 months, from around Jun 12 to Sep 28, peaking in August at about 79% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Jan 1.
August is the wettest month by volume, with 217 mm over about 24 wet days; February is the driest, with 0 mm.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rain on a day (%) | 0 | 0 | 0 | 3 | 10 | 24 | 59 | 74 | 37 | 8 | 0 | 0 |
| Rain days | 0 | 0 | 0 | 1 | 3 | 7 | 18 | 24 | 11 | 2 | 0 | 0 |
| Rain on a day (%) | Rain days | |
|---|---|---|
| Jan | 0 | 0 |
| Feb | 0 | 0 |
| Mar | 0 | 0 |
| Apr | 3 | 1 |
| May | 10 | 3 |
| Jun | 24 | 7 |
| Jul | 59 | 18 |
| Aug | 74 | 24 |
| Sep | 37 | 11 |
| Oct | 8 | 2 |
| Nov | 0 | 0 |
| Dec | 0 | 0 |
Monthly rainfall
Over a full year, Umm Hājar collects about 444 mm of rain across 66 wet days — roughly 37 mm in an average month.
It doesn’t fall evenly. August is the wettest month with 217 mm, while February is the driest at just 0 mm. The three wettest months alone bring about 90% of the year’s total.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rainfall (mm) | 0 | 0 | 0 | 2 | 10 | 24 | 117 | 217 | 67 | 8 | 0 | 0 |
| Rain days | 0 | 0 | 0 | 1 | 3 | 7 | 18 | 24 | 11 | 2 | 0 | 0 |
| Rainfall (mm) | Rain days | |
|---|---|---|
| Jan | 0 | 0 |
| Feb | 0 | 0 |
| Mar | 0 | 0 |
| Apr | 2 | 1 |
| May | 10 | 3 |
| Jun | 24 | 7 |
| Jul | 117 | 18 |
| Aug | 217 | 24 |
| Sep | 67 | 11 |
| Oct | 8 | 2 |
| Nov | 0 | 0 |
| Dec | 0 | 0 |
Clouds and sunshine
How often the daytime sky is clear, partly cloudy or overcast.
In Umm Hājar, 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 September 29 and lasts for 8.7 months, ending around June 20. The clearest month is November, when the sky is clear, mostly clear, or partly cloudy 85% of the time on average.
The cloudier part of the year begins around June 21 and lasts for 3.3 months, ending around September 28. The cloudiest month is August, when it is overcast or mostly cloudy 70% of the time.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Clearer (%) | 82 | 81 | 78 | 79 | 79 | 73 | 46 | 30 | 57 | 82 | 85 | 84 |
| Cloudier (%) | 18 | 19 | 22 | 21 | 21 | 27 | 54 | 70 | 43 | 18 | 15 | 16 |
| Clearer (%) | Cloudier (%) | |
|---|---|---|
| Jan | 82 | 18 |
| Feb | 81 | 19 |
| Mar | 78 | 22 |
| Apr | 79 | 21 |
| May | 79 | 21 |
| Jun | 73 | 27 |
| Jul | 46 | 54 |
| Aug | 30 | 70 |
| Sep | 57 | 43 |
| Oct | 82 | 18 |
| Nov | 85 | 15 |
| Dec | 84 | 16 |
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 7, brings about 12 h 48 min of light; the shortest, around January 1, only 11 h 12 min — a swing of roughly 1 h 36 min.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Daylight (h) | 11.3 | 11.6 | 11.9 | 12.3 | 12.6 | 12.8 | 12.7 | 12.4 | 12.1 | 11.7 | 11.4 | 11.2 |
| Sunrise (AM) | 6:12 | 6:09 | 5:54 | 5:33 | 5:19 | 5:18 | 5:25 | 5:32 | 5:33 | 5:35 | 5:45 | 6:01 |
| Sunset (PM) | 5:29 | 5:43 | 5:48 | 5:50 | 5:56 | 6:05 | 6:08 | 5:59 | 5:38 | 5:17 | 5:08 | 5:14 |
| Daylight (h) | Sunrise (AM) | Sunset (PM) | |
|---|---|---|---|
| Jan | 11.3 | 6:12 | 5:29 |
| Feb | 11.6 | 6:09 | 5:43 |
| Mar | 11.9 | 5:54 | 5:48 |
| Apr | 12.3 | 5:33 | 5:50 |
| May | 12.6 | 5:19 | 5:56 |
| Jun | 12.8 | 5:18 | 6:05 |
| Jul | 12.7 | 5:25 | 6:08 |
| Aug | 12.4 | 5:32 | 5:59 |
| Sep | 12.1 | 5:33 | 5:38 |
| Oct | 11.7 | 5:35 | 5:17 |
| Nov | 11.4 | 5:45 | 5:08 |
| Dec | 11.2 | 6:01 | 5:14 |
Sunny days
How many genuinely sunny days each month brings — days the sky stays clear or mostly clear — banded into plain-language zones.
Umm Hājar averages about 17 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 2 and 23 days.
The sunnier stretch runs 8.5 months, from around Sep 30 to Jun 14. The sunniest month is December, with roughly 23 sunny days (bright).
The greyest month is August, down near 3 sunny days — about 89% fewer than the December peak.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sunny days | 22 | 19 | 20 | 19 | 20 | 15 | 5 | 3 | 11 | 21 | 22 | 23 |
| Sky | Bright | Bright | Bright | Bright | Bright | Bright | Gloomy | Gloomy | Mixed | Bright | Bright | Bright |
| Sunny days | Sky | |
|---|---|---|
| Jan | 22 | Bright |
| Feb | 19 | Bright |
| Mar | 20 | Bright |
| Apr | 19 | Bright |
| May | 20 | Bright |
| Jun | 15 | Bright |
| Jul | 5 | Gloomy |
| Aug | 3 | Gloomy |
| Sep | 11 | Mixed |
| Oct | 21 | Bright |
| Nov | 22 | Bright |
| Dec | 23 | Bright |
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 Umm Hājar, how humid it feels changes dramatically over the year.
The more humid part of the year lasts 4.9 months, from around May 21 to October 16. The muggiest month is July, when the air feels humid, muggy or worse about 97% of the time.
The most comfortable stretch runs from around October 17 to May 20, and March is the most comfortable month — the air is dry or comfortable 100% of the time.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Dry (%) | 100 | 100 | 99 | 84 | 48 | 11 | 1 | 0 | 2 | 46 | 97 | 100 |
| Comfortable (%) | 0 | 0 | 1 | 9 | 18 | 17 | 3 | 0 | 2 | 11 | 1 | 0 |
| Humid (%) | 0 | 0 | 0 | 6 | 21 | 31 | 7 | 0 | 5 | 16 | 1 | 0 |
| Muggy (%) | 0 | 0 | 0 | 2 | 12 | 31 | 28 | 2 | 17 | 17 | 0 | 0 |
| Oppressive (%) | 0 | 0 | 0 | 0 | 1 | 10 | 62 | 96 | 74 | 10 | 0 | 0 |
| Miserable (%) | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 2 | 1 | 0 | 0 | 0 |
| Dry (%) | Comfortable (%) | Humid (%) | Muggy (%) | Oppressive (%) | Miserable (%) | |
|---|---|---|---|---|---|---|
| Jan | 100 | 0 | 0 | 0 | 0 | 0 |
| Feb | 100 | 0 | 0 | 0 | 0 | 0 |
| Mar | 99 | 1 | 0 | 0 | 0 | 0 |
| Apr | 84 | 9 | 6 | 2 | 0 | 0 |
| May | 48 | 18 | 21 | 12 | 1 | 0 |
| Jun | 11 | 17 | 31 | 31 | 10 | 0 |
| Jul | 1 | 3 | 7 | 28 | 62 | 0 |
| Aug | 0 | 0 | 0 | 2 | 96 | 2 |
| Sep | 2 | 2 | 5 | 17 | 74 | 1 |
| Oct | 46 | 11 | 16 | 17 | 10 | 0 |
| Nov | 97 | 1 | 1 | 0 | 0 | 0 |
| Dec | 100 | 0 | 0 | 0 | 0 | 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.
Across the year, average wind speed in Umm Hājar is typically calm, near 10 km/h, and varies little with the seasons.
The windier part of the year lasts 5.8 months, from around Nov 12 to May 8. The windiest month is March, averaging about 12 km/h (calm).
The calmer part of the year runs from around Jul 16 to Nov 11, with September the calmest month at about 7 km/h.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Wind speed (km/h) | 11 | 11 | 12 | 11 | 10 | 10 | 10 | 8 | 7 | 8 | 10 | 10 |
| Feels | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm |
| Wind speed (km/h) | Feels | |
|---|---|---|
| Jan | 11 | calm |
| Feb | 11 | calm |
| Mar | 12 | calm |
| Apr | 11 | calm |
| May | 10 | calm |
| Jun | 10 | calm |
| Jul | 10 | calm |
| Aug | 8 | calm |
| Sep | 7 | calm |
| Oct | 8 | calm |
| Nov | 10 | calm |
| Dec | 10 | calm |
Hazard calendar for Umm Hājar
When the seasonal hazards worth planning around — the rainy season, tropical-cyclone risk and dust haze — are active through the year.
Umm Hājar sees seasonal dust haze (March–October), heaviest in April.
Best time to visit Umm Hājar
To characterize how pleasant the weather is in Umm Hājar throughout the year, we compute two travel scores — one for general sightseeing, one for beach and pool weather.
The travel score favors clear, rainless days with daytime highs between 18°C and 28°C. Based on this score, the best time of year to visit Umm Hājar for general outdoor tourist activities is from mid December to late January, with a peak score in the first week of January.
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) | 4.4 | 2.6 | 0.6 | 0.0 | 0.0 | 0.5 | 2.0 | 2.8 | 2.7 | 1.5 | 2.2 | 3.9 |
| Rating | fair | poor | poor | poor | poor | poor | poor | poor | poor | poor | poor | fair |
| Travel score (0–10) | Rating | |
|---|---|---|
| Jan | 4.4 | fair |
| Feb | 2.6 | poor |
| Mar | 0.6 | poor |
| Apr | 0.0 | poor |
| May | 0.0 | poor |
| Jun | 0.5 | poor |
| Jul | 2.0 | poor |
| Aug | 2.8 | poor |
| Sep | 2.7 | poor |
| Oct | 1.5 | poor |
| Nov | 2.2 | poor |
| 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 Umm Hājar for hot-weather activities is from late November to mid February, with a peak score in the first week of January.
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 Umm Hājar, 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 April (highs near 41°C), the essentials are light clothes and sun protection. In the cold season around August (highs near 32°C), pack light clothes, rain gear and sun protection.
In April, Umm Hājar sees daytime highs around 41°C and nights near 26°C. Pack light clothes and sun protection.
UV index (midday) in Umm Hājar 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 Umm Hājar peaks around August 16 at about 13 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 16 at about 8 (very high).
The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 9 | 12 | 11 | 10 | 10 | 11 | 11 | 13 | 11 | 11 | 9 | 8 |
| Level | Very high | Extreme | Extreme | Extreme | Very high | Extreme | Extreme | Extreme | Extreme | Extreme | Very high | Very high |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 9 | Very high |
| Feb | 12 | Extreme |
| Mar | 11 | Extreme |
| Apr | 10 | Extreme |
| May | 10 | Very high |
| Jun | 11 | Extreme |
| Jul | 11 | Extreme |
| Aug | 13 | Extreme |
| Sep | 11 | Extreme |
| Oct | 11 | Extreme |
| Nov | 9 | Very high |
| Dec | 8 | Very high |
Average hourly UV index in Umm Hājar
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 August the burn window is concentrated in the middle of the day: about 8.5 hours a day reach index 3 (protection recommended), and 6.5 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) | 7 | 7.5 | 7.5 | 7.5 | 7.5 | 8 | 8 | 8.5 | 7.5 | 7.5 | 7 | 6.5 |
| UV ≥ 6 (h/day) | 4.5 | 5.5 | 5.5 | 5.5 | 5 | 5.5 | 6 | 6.5 | 5.5 | 5.5 | 4.5 | 3.5 |
| UV ≥ 3 (h/day) | UV ≥ 6 (h/day) | |
|---|---|---|
| Jan | 7 | 4.5 |
| Feb | 7.5 | 5.5 |
| Mar | 7.5 | 5.5 |
| Apr | 7.5 | 5.5 |
| May | 7.5 | 5 |
| Jun | 8 | 5.5 |
| Jul | 8 | 6 |
| Aug | 8.5 | 6.5 |
| Sep | 7.5 | 5.5 |
| Oct | 7.5 | 5.5 |
| Nov | 7 | 4.5 |
| Dec | 6.5 | 3.5 |
Air quality in Umm Hājar 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 Umm Hājar is worst in March — around 71 µg/m³ PM2.5 (unhealthy), about 3.4× the cleanest month (September, 21 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) | 45 | 53 | 71 | 53 | 38 | 37 | 30 | 21 | 21 | 28 | 26 | 35 |
| Level | Poor | Poor | Unhealthy | Poor | Poor | Poor | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 45 | Poor |
| Feb | 53 | Poor |
| Mar | 71 | Unhealthy |
| Apr | 53 | Poor |
| May | 38 | Poor |
| Jun | 37 | Poor |
| Jul | 30 | Moderate |
| Aug | 21 | Moderate |
| Sep | 21 | Moderate |
| Oct | 28 | Moderate |
| Nov | 26 | Moderate |
| Dec | 35 | Moderate |
Growing season
Umm Hājar is frost-free year round — even the coldest nights rarely reach freezing, so there is no start or end to the growing season.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Frost-free chance (%) | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 |
| Frost nights | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Frost-free chance (%) | Frost nights | |
|---|---|---|
| Jan | 100 | 0 |
| Feb | 100 | 0 |
| Mar | 100 | 0 |
| Apr | 100 | 0 |
| May | 100 | 0 |
| Jun | 100 | 0 |
| Jul | 100 | 0 |
| Aug | 100 | 0 |
| Sep | 100 | 0 |
| Oct | 100 | 0 |
| Nov | 100 | 0 |
| Dec | 100 | 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. Umm Hājar banks about 7,251 degree days a year, and the running total — which growers use to time plantings and predict maturity — climbs fastest around May.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Growing degree days (°C·days) | 472 | 500 | 660 | 714 | 750 | 695 | 616 | 544 | 575 | 653 | 574 | 500 |
| Growing degree days (°C·days) | |
|---|---|
| Jan | 472 |
| Feb | 500 |
| Mar | 660 |
| Apr | 714 |
| May | 750 |
| Jun | 695 |
| Jul | 616 |
| Aug | 544 |
| Sep | 575 |
| Oct | 653 |
| Nov | 574 |
| Dec | 500 |
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.
Umm Hājar receives about 6.4 kWh/m² a day of solar energy on average — intense — with a clear seasonal swing between 5.4 and 7.4 kWh/m².
The brighter stretch of the year lasts 4.7 months, from around Feb 4 to Jun 25. The brightest month is April, averaging about 7.3 kWh/m² (intense).
The dimmest month is August, down near 5.5 kWh/m² — roughly 25% less than the April peak.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Solar energy (kWh/m²) | 6.1 | 6.6 | 7.2 | 7.4 | 7.0 | 6.6 | 5.9 | 5.4 | 6.2 | 6.3 | 6.2 | 5.9 |
| Level | Intense | Intense | Intense | Intense | Intense | Intense | Bright | Bright | Intense | Intense | Intense | Bright |
| Solar energy (kWh/m²) | Level | |
|---|---|---|
| Jan | 6.1 | Intense |
| Feb | 6.6 | Intense |
| Mar | 7.2 | Intense |
| Apr | 7.4 | Intense |
| May | 7.0 | Intense |
| Jun | 6.6 | Intense |
| Jul | 5.9 | Bright |
| Aug | 5.4 | Bright |
| Sep | 6.2 | Intense |
| Oct | 6.3 | Intense |
| Nov | 6.2 | Intense |
| Dec | 5.9 | Bright |
Where is Umm Hājar?
Umm Hājar sits at 13.3°N, 19.7°E, 397 m above sea level, in Chad. The nearest listed city is Mangalmé, 105 km away.
Topography around Umm Hājar
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Umm Hājar.
Within 3 km, the terrain around Umm Hājar has only modest variations in elevation — a maximum elevation change of 11 m around an average of 390 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 43 m; within 80 km, significant variations in elevation — a maximum elevation change of 295 m.
The land around Umm Hājar is covered by grassland (78%) within 3 km, grassland (91%) within 16 km, and grassland (92%) within 80 km.
Chad travel facts
- Travel advisory
- Level 4
- Do Not Travel
- Power plugs
- Type C / D / E / F
- 220 V · 50 Hz
- Prices
- ≈ 35% of US
- price level, 2025
- GDP per capita
- $1,022
- 2025
- Happiness
- 4.4 / 10
- World Happiness, 2025
- Safe drinking water
- 6%
- of population, 2024
- Road deaths
- 32.4
- per 100k/yr, 2019
- Income group
- Low
- World Bank
- 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 Umm Hājar (13.2954°, 19.6966°, elevation 397 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).