Climate and average weather in Darreh Shahr
In Darreh Shahr, the summers are sweltering, dry, and clear and the winters are cool, snowy, and mostly clear.
Over the course of the year, the temperature in Darreh Shahr typically varies from 1°C to 39°C, and is rarely below -4°C or above 42°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 Darreh Shahr for warm-weather activities are from late March to mid May and early October to mid November.
- Hottest
- Jul
- 39°
- Coldest
- Jan
- 1°
- Wettest
- Jan
- 93 mm
- Driest
- Jul
- 0 mm
- Rain / yr
- 535 mm
- 58 wet days
- Daylight
- 9.8–14.2 h
- shortest–longest
- Elevation
- 667 m
- 33.1°N
- Clearest
- Aug
- 4% cloud
Darreh Shahr is city in Ilam Province, Iran.
- Density
- 8,184/km²
- people per km²
- Founded
- 1964
Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.
Darreh Shahr 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 late March to mid May.
Temperature through the year
Daily average highs and lows in Darreh Shahr, from 1991–2020 of climate data. The shaded bands show the range most days fall in — 10th to 90th percentile.
The hot season lasts 4.0 months, from May 27 to September 25, with daily high temperatures above 32°C. The hottest month of the year in Darreh Shahr is July, with an average high of 39°C and low of 21°C.
The cool season lasts 3.5 months, from November 24 to March 8, with daily high temperatures below 16°C. The coldest month of the year in Darreh Shahr is January, with an average low of 1°C and high of 11°C.
Days typically run about 14°C warmer than nights, with the widest day–night swing (around 19°C) in September.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high (°C) | 11 | 13 | 17 | 22 | 29 | 36 | 39 | 39 | 34 | 27 | 18 | 13 |
| Avg low (°C) | 1 | 2 | 5 | 10 | 14 | 18 | 21 | 20 | 16 | 11 | 6 | 2 |
| Avg high (°C) | Avg low (°C) | |
|---|---|---|
| Jan | 11 | 1 |
| Feb | 13 | 2 |
| Mar | 17 | 5 |
| Apr | 22 | 10 |
| May | 29 | 14 |
| Jun | 36 | 18 |
| Jul | 39 | 21 |
| Aug | 39 | 20 |
| Sep | 34 | 16 |
| Oct | 27 | 11 |
| Nov | 18 | 6 |
| Dec | 13 | 2 |
How hot and cold Darreh Shahr 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, Darreh Shahr feels like about 39°C (around July 21). About 122 days a year carry some heat stress, and 30 of them tip into dangerous heat (feels-like above 39°C), peaking in July.
On the coldest nights, wind chill pulls the feels-like down to about -1°C (around January 20), with roughly 44 freezing days a year (feels-like at or below 0°C), worst in January.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Feels-like high (°C) | 11 | 12 | 17 | 22 | 29 | 36 | 39 | 39 | 34 | 27 | 18 | 13 |
| Air high (°C) | 11 | 13 | 17 | 22 | 29 | 36 | 39 | 39 | 34 | 27 | 18 | 13 |
| Feels-like low (°C) | -1 | 1 | 4 | 9 | 14 | 18 | 21 | 20 | 16 | 11 | 5 | 1 |
| Air low (°C) | 1 | 2 | 5 | 10 | 14 | 18 | 21 | 20 | 16 | 11 | 6 | 2 |
| Feels-like high (°C) | Air high (°C) | Feels-like low (°C) | Air low (°C) | |
|---|---|---|---|---|
| Jan | 11 | 11 | -1 | 1 |
| Feb | 12 | 13 | 1 | 2 |
| Mar | 17 | 17 | 4 | 5 |
| Apr | 22 | 22 | 9 | 10 |
| May | 29 | 29 | 14 | 14 |
| Jun | 36 | 36 | 18 | 18 |
| Jul | 39 | 39 | 21 | 21 |
| Aug | 39 | 39 | 20 | 20 |
| Sep | 34 | 34 | 16 | 16 |
| Oct | 27 | 27 | 11 | 11 |
| Nov | 18 | 18 | 5 | 6 |
| Dec | 13 | 13 | 1 | 2 |
Average hourly temperature in Darreh Shahr
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 39°C, and coldest before dawn in January, near 1°C.
Darreh Shahr weather by month
Every month at a glance. Click a month for its detailed page.
| Month | High / Low (°C) | Rainfall (mm) | Wet days | Snow days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|---|
| Jan | 11° / 1° | 93 | 9.6 | 2.3 | 10.1 | 2.6 |
| Feb | 13° / 2° | 79 | 9.4 | 1 | 10.8 | 3.6 |
| Mar | 17° / 5° | 92 | 8.7 | 0.1 | 11.7 | 5.7 |
| Apr | 22° / 10° | 68 | 7.6 | 0 | 12.8 | 7.3 |
| May | 29° / 14° | 16 | 3.2 | 0 | 13.7 | 6.6 |
| Jun | 36° / 18° | 0 | 0.1 | 0 | 14.1 | 2.9 |
| Jul | 39° / 21° | 0 | 0 | 0 | 14 | 0.8 |
| Aug | 39° / 20° | 0 | 0 | 0 | 13.2 | 1.0 |
| Sep | 34° / 16° | 1 | 0.1 | 0 | 12.2 | 4.1 |
| Oct | 27° / 11° | 27 | 3.1 | 0 | 11.2 | 7.7 |
| Nov | 18° / 6° | 73 | 7.2 | 0 | 10.3 | 6.3 |
| Dec | 13° / 2° | 87 | 8.5 | 0.6 | 9.8 | 3.7 |
Chance of rain
How likely it is to rain on a typical day, and how that shifts across the wetter and drier seasons.
Darreh Shahr gets about 535 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 6.5 months, from around Oct 23 to May 8, peaking in February at about 35% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Jun 17.
January is the wettest month by volume, with 93 mm over about 10 wet days; July is the driest, with 0 mm. Some of the cold-season precipitation falls as snow.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rain on a day (%) | 30 | 33 | 29 | 25 | 10 | 0 | 0 | 0 | 0 | 10 | 24 | 28 |
| Rain days | 10 | 9 | 9 | 8 | 3 | 0 | 0 | 0 | 0 | 3 | 7 | 9 |
| Rain on a day (%) | Rain days | |
|---|---|---|
| Jan | 30 | 10 |
| Feb | 33 | 9 |
| Mar | 29 | 9 |
| Apr | 25 | 8 |
| May | 10 | 3 |
| Jun | 0 | 0 |
| Jul | 0 | 0 |
| Aug | 0 | 0 |
| Sep | 0 | 0 |
| Oct | 10 | 3 |
| Nov | 24 | 7 |
| Dec | 28 | 9 |
Monthly rainfall
Over a full year, Darreh Shahr collects about 535 mm of rain across 58 wet days — roughly 45 mm in an average month.
It doesn’t fall evenly. January is the wettest month with 93 mm, while July is the driest at just 0 mm. The three wettest months alone bring about 51% of the year’s total, and some of the cold-season precipitation falls as snow.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rainfall (mm) | 93 | 79 | 92 | 68 | 16 | 0 | 0 | 0 | 1 | 27 | 73 | 87 |
| Rain days | 10 | 9 | 9 | 8 | 3 | 0 | 0 | 0 | 0 | 3 | 7 | 9 |
| Snow days | 2 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 |
| Rainfall (mm) | Rain days | Snow days | |
|---|---|---|---|
| Jan | 93 | 10 | 2 |
| Feb | 79 | 9 | 1 |
| Mar | 92 | 9 | 0 |
| Apr | 68 | 8 | 0 |
| May | 16 | 3 | 0 |
| Jun | 0 | 0 | 0 |
| Jul | 0 | 0 | 0 |
| Aug | 0 | 0 | 0 |
| Sep | 1 | 0 | 0 |
| Oct | 27 | 3 | 0 |
| Nov | 73 | 7 | 0 |
| Dec | 87 | 9 | 1 |
Snow in Darreh Shahr
Average snowy days through the year, the snow-season span, and estimated snowfall — for ski trips and the perennial 'will there be snow at Christmas?' question.
Darreh Shahr averages about 4 snowy days a year. Snow season runs roughly Dec 9 to Mar 3 — about 2.8 months.
January is snowiest, with roughly 2 days of snow and an estimated 14 cm of snowfall. Over the year that adds up to an estimated 22 cm of snow.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Snow days | 2 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 |
| Snowfall (cm) | 14 | 5 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 3 |
| Snow days | Snowfall (cm) | |
|---|---|---|
| Jan | 2 | 14 |
| Feb | 1 | 5 |
| Mar | 0 | 0 |
| Apr | 0 | 0 |
| May | 0 | 0 |
| Jun | 0 | 0 |
| Jul | 0 | 0 |
| Aug | 0 | 0 |
| Sep | 0 | 0 |
| Oct | 0 | 0 |
| Nov | 0 | 0 |
| Dec | 1 | 3 |
Clouds and sunshine
How often the daytime sky is clear, partly cloudy or overcast.
In Darreh Shahr, 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 13 and lasts for 5.4 months, ending around October 22. The clearest month is July, when the sky is clear, mostly clear, or partly cloudy 100% of the time on average.
The cloudier part of the year begins around October 23 and lasts for 6.6 months, ending around May 12. The cloudiest month is January, when it is overcast or mostly cloudy 41% of the time.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Clearer (%) | 59 | 62 | 64 | 69 | 81 | 98 | 100 | 100 | 99 | 84 | 67 | 59 |
| Cloudier (%) | 41 | 38 | 36 | 31 | 19 | 2 | 0 | 0 | 1 | 16 | 33 | 41 |
| Clearer (%) | Cloudier (%) | |
|---|---|---|
| Jan | 59 | 41 |
| Feb | 62 | 38 |
| Mar | 64 | 36 |
| Apr | 69 | 31 |
| May | 81 | 19 |
| Jun | 98 | 2 |
| Jul | 100 | 0 |
| Aug | 100 | 0 |
| Sep | 99 | 1 |
| Oct | 84 | 16 |
| Nov | 67 | 33 |
| Dec | 59 | 41 |
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 12, brings about 14 h 12 min of light; the shortest, around January 1, only 9 h 48 min — a swing of roughly 4 h 24 min.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Daylight (h) | 10.1 | 10.8 | 11.7 | 12.8 | 13.7 | 14.1 | 14.0 | 13.2 | 12.2 | 11.2 | 10.3 | 9.8 |
| Sunrise (AM) | 7:29 | 7:12 | 6:38 | 5:56 | 5:26 | 5:15 | 5:26 | 5:47 | 6:09 | 6:31 | 6:58 | 7:22 |
| Sunset (PM) | 5:31 | 5:58 | 6:23 | 6:45 | 7:08 | 7:26 | 7:26 | 7:02 | 6:21 | 5:40 | 5:14 | 5:11 |
| Daylight (h) | Sunrise (AM) | Sunset (PM) | |
|---|---|---|---|
| Jan | 10.1 | 7:29 | 5:31 |
| Feb | 10.8 | 7:12 | 5:58 |
| Mar | 11.7 | 6:38 | 6:23 |
| Apr | 12.8 | 5:56 | 6:45 |
| May | 13.7 | 5:26 | 7:08 |
| Jun | 14.1 | 5:15 | 7:26 |
| Jul | 14.0 | 5:26 | 7:26 |
| Aug | 13.2 | 5:47 | 7:02 |
| Sep | 12.2 | 6:09 | 6:21 |
| Oct | 11.2 | 6:31 | 5:40 |
| Nov | 10.3 | 6:58 | 5:14 |
| Dec | 9.8 | 7:22 | 5:11 |
Sunny days
How many genuinely sunny days each month brings — days the sky stays clear or mostly clear — banded into plain-language zones.
Darreh Shahr averages about 21 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 12 and 30 days.
The sunnier stretch runs 5.2 months, from around May 18 to Oct 23. The sunniest month is June, with roughly 29 sunny days (brilliant).
The greyest month is January, down near 13 sunny days — about 55% fewer than the June peak.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sunny days | 13 | 13 | 15 | 16 | 20 | 28 | 30 | 31 | 29 | 23 | 16 | 14 |
| Sky | Mixed | Mixed | Mixed | Bright | Bright | Brilliant | Brilliant | Brilliant | Brilliant | Bright | Bright | Mixed |
| Sunny days | Sky | |
|---|---|---|
| Jan | 13 | Mixed |
| Feb | 13 | Mixed |
| Mar | 15 | Mixed |
| Apr | 16 | Bright |
| May | 20 | Bright |
| Jun | 28 | Brilliant |
| Jul | 30 | Brilliant |
| Aug | 31 | Brilliant |
| Sep | 29 | Brilliant |
| Oct | 23 | Bright |
| Nov | 16 | Bright |
| Dec | 14 | 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 Darreh Shahr, the air stays dry or comfortable essentially all year. Even in April, the muggiest month, it feels humid or worse only about 0% 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 (%) | 100 | 100 | 100 | 100 | 98 | 100 | 100 | 100 | 100 | 100 | 100 | 100 |
| Comfortable (%) | 0 | 0 | 0 | 0 | 2 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Dry (%) | Comfortable (%) | |
|---|---|---|
| Jan | 100 | 0 |
| Feb | 100 | 0 |
| Mar | 100 | 0 |
| Apr | 100 | 0 |
| May | 98 | 2 |
| Jun | 100 | 0 |
| Jul | 100 | 0 |
| Aug | 100 | 0 |
| Sep | 100 | 0 |
| Oct | 100 | 0 |
| Nov | 100 | 0 |
| Dec | 100 | 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 Darreh Shahr is steady company: average speeds sit near 6 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) | 6 | 6 | 6 | 6 | 6 | 7 | 6 | 6 | 6 | 6 | 5 | 5 |
| Feels | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm |
| Wind speed (km/h) | Feels | |
|---|---|---|
| Jan | 6 | calm |
| Feb | 6 | calm |
| Mar | 6 | calm |
| Apr | 6 | calm |
| May | 6 | calm |
| Jun | 7 | calm |
| Jul | 6 | calm |
| Aug | 6 | calm |
| Sep | 6 | calm |
| Oct | 6 | calm |
| Nov | 5 | calm |
| Dec | 5 | calm |
Hazard calendar for Darreh Shahr
When the seasonal hazards worth planning around — the rainy season, tropical-cyclone risk and dust haze — are active through the year.
Darreh Shahr's rainy season runs November–April, when most of the year's rain falls.
Darreh Shahr sees seasonal dust haze (March–May), heaviest in May.
Best time to visit Darreh Shahr
To characterize how pleasant the weather is in Darreh Shahr throughout the year, we compute two travel scores — one for general sightseeing, one for beach and pool weather.
Around mid May, Darreh Shahr is still near the tail of its best-weather window — great conditions with the peak-season crowds already thinning.
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 Darreh Shahr for general outdoor tourist activities run from late March to mid May and again from early October to mid November, with a peak score in the third week of October.
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) | 2.7 | 3.6 | 5.7 | 7.3 | 6.6 | 3.0 | 0.9 | 1.1 | 4.1 | 7.6 | 6.2 | 3.8 |
| Rating | poor | fair | good | good | good | poor | poor | poor | fair | ideal | good | fair |
| Travel score (0–10) | Rating | |
|---|---|---|
| Jan | 2.7 | poor |
| Feb | 3.6 | fair |
| Mar | 5.7 | good |
| Apr | 7.3 | good |
| May | 6.6 | good |
| Jun | 3.0 | poor |
| Jul | 0.9 | poor |
| Aug | 1.1 | poor |
| Sep | 4.1 | fair |
| Oct | 7.6 | ideal |
| Nov | 6.2 | good |
| Dec | 3.8 | fair |
The beach/pool score favors clear, rainless days with daytime highs between 24°C and 34°C. Based on this score, the best times of year to visit Darreh Shahr for hot-weather activities run from early May to mid June and again from mid September to late October, with a peak score in the first week of October.
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 Darreh Shahr, 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 39°C), the essentials are light clothes and sun protection. In the cold season around January (highs near 11°C), pack a warm layer and rain gear.
In July, Darreh Shahr sees daytime highs around 39°C and nights near 21°C. Pack light clothes and sun protection.
UV index (midday) in Darreh Shahr 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 Darreh Shahr peaks around June 17 at about 10 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near January 13 at about 3 (moderate).
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) | 3 | 4 | 5 | 7 | 10 | 11 | 10 | 10 | 7 | 6 | 4 | 3 |
| Level | Moderate | Moderate | High | High | Very high | Extreme | Very high | Very high | Very high | High | Moderate | Moderate |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 3 | Moderate |
| Feb | 4 | Moderate |
| Mar | 5 | High |
| Apr | 7 | High |
| May | 10 | Very high |
| Jun | 11 | Extreme |
| Jul | 10 | Very high |
| Aug | 10 | Very high |
| Sep | 7 | Very high |
| Oct | 6 | High |
| Nov | 4 | Moderate |
| Dec | 3 | Moderate |
Average hourly UV index in Darreh Shahr
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 June the burn window is concentrated in the middle of the day: about 8.5 hours a day reach index 3 (protection recommended), and 6 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) | 1.5 | 3.5 | 5.5 | 6.5 | 8 | 8.5 | 8.5 | 8 | 7 | 5.5 | 3.5 | 2 |
| UV ≥ 6 (h/day) | 0 | 0 | 0 | 3 | 5.5 | 6 | 5.5 | 5.5 | 3.5 | 1.5 | 0 | 0 |
| UV ≥ 3 (h/day) | UV ≥ 6 (h/day) | |
|---|---|---|
| Jan | 1.5 | 0 |
| Feb | 3.5 | 0 |
| Mar | 5.5 | 0 |
| Apr | 6.5 | 3 |
| May | 8 | 5.5 |
| Jun | 8.5 | 6 |
| Jul | 8.5 | 5.5 |
| Aug | 8 | 5.5 |
| Sep | 7 | 3.5 |
| Oct | 5.5 | 1.5 |
| Nov | 3.5 | 0 |
| Dec | 2 | 0 |
Air quality in Darreh Shahr 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 Darreh Shahr is worst in April — around 42 µg/m³ PM2.5 (poor), about 1.7× the cleanest month (November, 26 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) | 27 | 32 | 39 | 42 | 41 | 35 | 35 | 33 | 32 | 30 | 26 | 26 |
| Level | Moderate | Moderate | Poor | Poor | Poor | Poor | Poor | Moderate | Moderate | Moderate | Moderate | Moderate |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 27 | Moderate |
| Feb | 32 | Moderate |
| Mar | 39 | Poor |
| Apr | 42 | Poor |
| May | 41 | Poor |
| Jun | 35 | Poor |
| Jul | 35 | Poor |
| Aug | 33 | Moderate |
| Sep | 32 | Moderate |
| Oct | 30 | Moderate |
| Nov | 26 | Moderate |
| Dec | 26 | Moderate |
Growing season
Darreh Shahr is mild enough that a frost-free day stays more likely than not even in midwinter. Nights are reliably above freezing from about March 10 to November 22 (258 days); outside that window a hard frost is an occasional risk.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Frost-free chance (%) | 58 | 72 | 93 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 94 | 73 |
| Frost nights | 31 | 28 | 7 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 8 | 31 |
| Frost-free chance (%) | Frost nights | |
|---|---|---|
| Jan | 58 | 31 |
| Feb | 72 | 28 |
| Mar | 93 | 7 |
| Apr | 100 | 0 |
| May | 100 | 0 |
| Jun | 100 | 0 |
| Jul | 100 | 0 |
| Aug | 100 | 0 |
| Sep | 100 | 0 |
| Oct | 100 | 0 |
| Nov | 94 | 8 |
| Dec | 73 | 31 |
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. Darreh Shahr banks about 3,065 degree days a year, and the running total — which growers use to time plantings and predict maturity — climbs fastest around July.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Growing degree days (°C·days) | 0 | 0 | 35 | 175 | 353 | 503 | 615 | 599 | 445 | 279 | 60 | 0 |
| Growing degree days (°C·days) | |
|---|---|
| Jan | 0 |
| Feb | 0 |
| Mar | 35 |
| Apr | 175 |
| May | 353 |
| Jun | 503 |
| Jul | 615 |
| Aug | 599 |
| Sep | 445 |
| Oct | 279 |
| Nov | 60 |
| 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.
Darreh Shahr receives about 5.6 kWh/m² a day of solar energy on average — bright — with a clear seasonal swing between 2.8 and 8.1 kWh/m².
The brighter stretch of the year lasts 6.3 months, from around Mar 25 to Oct 2. The brightest month is June, averaging about 8.0 kWh/m² (intense).
The dimmest month is December, down near 2.8 kWh/m² — roughly 65% less than the June peak.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Solar energy (kWh/m²) | 3.0 | 4.0 | 5.2 | 6.5 | 7.4 | 8.1 | 7.8 | 7.4 | 6.4 | 4.9 | 3.5 | 2.8 |
| Level | Moderate | Bright | Bright | Intense | Intense | Intense | Intense | Intense | Intense | Bright | Moderate | Moderate |
| Solar energy (kWh/m²) | Level | |
|---|---|---|
| Jan | 3.0 | Moderate |
| Feb | 4.0 | Bright |
| Mar | 5.2 | Bright |
| Apr | 6.5 | Intense |
| May | 7.4 | Intense |
| Jun | 8.1 | Intense |
| Jul | 7.8 | Intense |
| Aug | 7.4 | Intense |
| Sep | 6.4 | Intense |
| Oct | 4.9 | Bright |
| Nov | 3.5 | Moderate |
| Dec | 2.8 | Moderate |
Where is Darreh Shahr?
Darreh Shahr sits at 33.1°N, 47.4°E, 667 m above sea level, in Iran. The nearest listed city is Ābdānān, 17 km away.
Topography around Darreh Shahr
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Darreh Shahr.
Within 3 km, the terrain around Darreh Shahr has significant variations in elevation — a maximum elevation change of 318 m around an average of 686 m above sea level; within 16 km, very significant variations in elevation — a maximum elevation change of 1,666 m; within 80 km, extreme variations in elevation — a maximum elevation change of 2,732 m.
The land around Darreh Shahr is covered by cropland (42%) and grassland (39%) within 3 km, grassland (62%) and cropland (22%) within 16 km, and grassland (63%) and bare terrain (21%) within 80 km.
Iran travel facts
- Travel advisory
- Level 4
- Do Not Travel
- Power plugs
- Type C / F
- 220 V · 50 Hz
- Prices
- ≈ 352% of US
- price level, 2025
- GDP per capita
- $3,924
- 2025
- Happiness
- 5.2 / 10
- World Happiness, 2025
- Safe drinking water
- 94%
- of population, 2024
- Homicide rate
- 2.4
- per 100k, 2014
- Road deaths
- 21.5
- per 100k/yr, 2019
- Income group
- Upper middle
- World Bank
- English
- Low
- EF EPI 492
- 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 Darreh Shahr (33.1445°, 47.3799°, elevation 667 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).