Semnan in Winter
In winter (December, January and February), Semnan sees average daytime highs around 9°C and overnight lows near 1°C, with 37 mm of precipitation over about 9 wet days across the season. It is the coldest season of the year and the wettest season of the year.
Across winter, daytime highs hold fairly steady around 9°C. The sky is clear or mostly clear about 58% of the time across winter, and the air most often feels dry.
Winter is Semnan's weakest season of the year to visit on our travel score. For the whole year in context, see Semnan's year-round climate.
- Avg daytime high
- 9°C
- coldest season of the year
- Avg overnight low
- 1°C
- Precipitation
- 37 mm
- 9 wet days
- Avg wind
- 8 km/h
- Travel score
- 2.3
- weakest season of the year
- Months
- Dec · Jan · Feb
Temperature in Semnan in Winter
Across winter, daytime highs hold fairly steady around 9°C.
A typical winter day in Semnan reaches about 9°C and drops to 1°C overnight. The warmest of the three months is February, the coolest January.
How winter really feels in Semnan
Once humidity and wind are folded in, winter brings about 0 days that feel above 32°C and 79 that feel at or below 0°C.
The story in winter is cold — wind chill drags the overnight "feels like" below the raw low.
Semnan weather by month
How the three winter months (December, January and February) compare with the rest of the year — the season's months are highlighted.
| Month | High / Low (°C) | Rainfall (mm) | Wet days | Snow days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|---|
| Jan | 8° / -0° | 12 | 3.2 | 1.7 | 9.9 | 1.6 |
| Feb | 10° / 1° | 14 | 2.9 | 1.4 | 10.7 | 2.9 |
| Mar | 16° / 6° | 18 | 3.9 | 0.9 | 11.7 | 5.7 |
| Apr | 22° / 11° | 13 | 2.7 | 0.1 | 12.9 | 8.0 |
| May | 28° / 17° | 5 | 1.3 | 0 | 13.9 | 7.6 |
| Jun | 33° / 21° | 1 | 0.3 | 0 | 14.4 | 4.5 |
| Jul | 36° / 24° | 1 | 0.3 | 0 | 14.2 | 2.9 |
| Aug | 35° / 23° | 1 | 0.3 | 0 | 13.3 | 3.8 |
| Sep | 30° / 18° | 2 | 0.5 | 0 | 12.2 | 6.8 |
| Oct | 23° / 12° | 5 | 1.1 | 0 | 11.1 | 8.8 |
| Nov | 15° / 6° | 11 | 3 | 0.2 | 10.1 | 5.4 |
| Dec | 9° / 1° | 10 | 3.1 | 0.9 | 9.6 | 2.3 |
Cloud cover in Winter
The sky is clear or mostly clear about 58% of the time across winter.
Chance of precipitation in Winter
Semnan gets around 37 mm of rain and snow over 9 wet days across winter. The line is the day-by-day chance of measurable precipitation.
Humidity in Winter
Most of winter feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Winter
Winds average 8 km/h across winter.
Sunrise & sunset in Winter
Daylight runs from about 9 h 48 min in early December to 11 h 06 min by late February. The lit band spans sunrise to sunset each day.
Solar energy in Winter
Average shortwave solar energy reaching the ground each day across winter, about 3.4 kWh/m².
Is winter a good time to visit Semnan?
Our two travel scores rate winter for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal), averaged across the three months.
winter is a weaker month for outdoor sightseeing in Semnan.
What to pack for Semnan in Winter
From winter's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In winter, Semnan sees daytime highs around 9°C and nights near 1°C. Pack a warm layer. Worth having: a heavy coat. About 9 days see rain.
UV index in Semnan in Winter
Clear-sky midday UV across winter averages around 4 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in Semnan peaks around July 19 at about 11 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near January 10 at about 3 (moderate).
The index reaches 3 or more — the level where the WHO recommends sun protection — in 11 months of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 3 | 5 | 5 | 8 | 10 | 10 | 11 | 10 | 8 | 6 | 4 | 3 |
| Level | Moderate | High | Moderate | Very high | Very high | Very high | Extreme | Extreme | Very high | High | Moderate | Moderate |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 3 | Moderate |
| Feb | 5 | High |
| Mar | 5 | Moderate |
| Apr | 8 | Very high |
| May | 10 | Very high |
| Jun | 10 | Very high |
| Jul | 11 | Extreme |
| Aug | 10 | Extreme |
| Sep | 8 | Very high |
| Oct | 6 | High |
| Nov | 4 | Moderate |
| Dec | 3 | Moderate |
Air quality in Semnan in Winter
Average fine-particle pollution (PM2.5) through the year — so you can see where winter falls, not just the annual average.
Air quality in Semnan is worst in December — around 46 µg/m³ PM2.5 (poor), about 2.1× the cleanest month (August, 22 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) | 43 | 41 | 38 | 40 | 34 | 23 | 23 | 22 | 28 | 32 | 39 | 46 |
| Level | Poor | Poor | Poor | Poor | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Poor | Poor |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 43 | Poor |
| Feb | 41 | Poor |
| Mar | 38 | Poor |
| Apr | 40 | Poor |
| May | 34 | Moderate |
| Jun | 23 | Moderate |
| Jul | 23 | Moderate |
| Aug | 22 | Moderate |
| Sep | 28 | Moderate |
| Oct | 32 | Moderate |
| Nov | 39 | Poor |
| Dec | 46 | Poor |
Where is Semnan?
Semnan sits at 35.6°N, 53.4°E, 1,148 m above sea level, in Iran. The nearest listed city is Mahdishahr, 15 km away.
Topography around Semnan
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Semnan.
Within 3 km, the terrain around Semnan has only modest variations in elevation — a maximum elevation change of 144 m around an average of 1,149 m above sea level; within 16 km, very significant variations in elevation — a maximum elevation change of 1,254 m; within 80 km, extreme variations in elevation — a maximum elevation change of 3,375 m.
The land around Semnan is covered by artificial surfaces (59%) and bare terrain (20%) within 3 km, bare terrain (84%) within 16 km, and bare terrain (67%) and grassland (22%) 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 Semnan (35.5769°, 53.392°, elevation 1,148 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.