Climate averages 1991–2020
Tehran weather
in December.
A cold, moderately wet month: the 10th warmest and the 8th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
December is a cold month in Tehran: daytime highs average 7.6°C and nights cool to about -2.2°C. By daytime temperature it is the 10th warmest of the 12 months.
Expect about 43 mm of rain on roughly 8 days, which makes December a moderately wet month (the 8th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 9 h 48 min on an average December day.
The nearest other city in this atlas is Tajrīsh (12 km away). In December its highs average 5.0°C, 2.7°C cooler than Tehran, with 43 mm of rain.
Among the 128 cities listed in Iran, Tehran ranks 89th of 128 for the warmest December highs and joint 76th of 128 for the driest December (rainfall, lowest first). The mean December high of those 128 cities is 10.9°C; Tehran is 3.3°C cooler than that mean.
From December to January, average highs fall by 2.3°C to 5.3°C, and monthly rainfall falls from 43 mm to 42 mm.
The annual picture
December in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Tehran climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 5.3°C-5.3°C | -5.3°C | 42 | 7.6 | 10.010 h |
| February | 7.4°C-3.5°C | -3.5°C | 49 | 8.5 | 10.911 h |
| March | 13.3°C1.6°C | 1.6°C | 62 | 9.5 | 11.912 h |
| April | 20.0°C8.0°C | 8.0°C | 51 | 9.5 | 13.113 h |
| May | 26.6°C14.0°C | 14.0°C | 22 | 5.0 | 14.014 h |
| June | 32.9°C20.4°C | 20.4°C | 5.8 | 1.6 | 14.515 h |
| July | 35.6°C24.5°C | 24.5°C | 4.6 | 1.2 | 14.314 h |
| August | 34.6°C23.4°C | 23.4°C | 4.2 | 0.8 | 13.514 h |
| September | 29.9°C18.6°C | 18.6°C | 4.7 | 0.9 | 12.412 h |
| October | 22.6°C12.0°C | 12.0°C | 21 | 4.1 | 11.311 h |
| November | 13.4°C3.8°C | 3.8°C | 45 | 7.1 | 10.310 h |
| December, selected | 7.6°C-2.2°C | -2.2°C | 43 | 7.5 | 9.810 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
December in nearby cities
- Tajrīsh in DecemberIran · 12 kmHigh 5.0°C · Low -4.6°C · 43 mm rain
- Eslamshahr in DecemberIran · 23 kmHigh 9.3°C · Low -1.0°C · 45 mm rain
- Bāghestān in DecemberIran · 27 kmHigh 9.2°C · Low -1.4°C · 43 mm rain
- Golestān in DecemberIran · 29 kmHigh 9.9°C · Low -0.3°C · 45 mm rain
- Qarchak in DecemberIran · 33 kmHigh 10.2°C · Low -0.1°C · 40 mm rain
- Shahrīār in DecemberIran · 33 kmHigh 8.5°C · Low -2.1°C · 37 mm rain
- Pākdasht in DecemberIran · 34 kmHigh 9.9°C · Low 0.6°C · 30 mm rain
- Pardīs in DecemberIran · 36 kmHigh 3.2°C · Low -4.7°C · 36 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Tehran) is explained once on the Tehran year overview and on the Sources, method and limits page.
Tajrīsh lies in the same rainfall cell, so its rainfall figures are identical to these; temperatures differ because they come from smaller 0.1° cells.