Mongolia Ulaanbaatar Weather in December — Climate Guide
December in Ulaanbaatar is low
Ulaanbaatar Weather in December — Quick Answer
As of 2026- Avg temp
- -13° / -23°
- Rainfall
- 2mm · 2 days
- Crowds
- Quiet
As of 2026, Ulaanbaatar in December averages a high of -13°C and low of -23°C with 2mm of rain over about 2 days. Deep midwinter — highs around -13°C, nights near -23°C. Full expedition cold-weather kit: heavy down parka, thermal base layers, insulated boots, hat, balaclava, lined gloves, hand warmers. Severe coal smog hangs over the city; an N95/FFP2 mask is strongly advised.
December is low for Ulaanbaatar.
December plunges Ulaanbaatar into full midwinter, with highs around -13°C and nights near -23°C, plus the shortest days of the year. It is, alongside January, the coldest and smoggiest stretch in the world's coldest capital.
The winter smog is at its heaviest: with heating at maximum, raw-coal smoke from the ger districts settles over the valley and PM2.5 readings run many times the WHO guideline. Add the cold and the short daylight, and outdoor time is genuinely uncomfortable. A high-grade mask and serious cold-weather gear are essential.
Travel score
Ulaanbaatar December Weather Stats
Avg High
-13°C
Avg Low
-23°C
Rainy Days
2
2mm total
Sunshine
5h
Daily avg
Humidity
68%
very cold and dry
UV Index
1
Low
Wind
8 km/h
Gusts 22
Crowds
Quiet
At attractions
December Sunrise & Sunset
Air Quality
PM2.5
125 μg/m³
PM10
165 μg/m³
Status
very poor
Feels-Like Temperature & Wind
Feels like
Daytime
-20°C
Nighttime
-30°C
Humidity and wind affect how the actual temperature feels.
Wind
8 km/h
Max gust 22 km/h
Activities Recommended for December
December Travel Pros & Cons
Pros
- Cheapest rates, empty sights
- Clear, blue-sky cold-snap days
- Snow-covered scenery (for the prepared)
Cons
- Among coldest months — nights near -23°C
- Heaviest winter smog of the year
- Shortest daylight
- Ger camps closed; no countryside
December Events & Festivals
- One of the coldest, smoggiest months — PM2.5 far above WHO limits
- Shortest days of the year
- Off-season — ger camps closed
Ulaanbaatar in December — Full Picture
December plunges Ulaanbaatar into full midwinter, with highs around -13°C and nights near -23°C, plus the shortest days of the year. It is, alongside January, the coldest and smoggiest stretch in the world's coldest capital.
The winter smog is at its heaviest: with heating at maximum, raw-coal smoke from the ger districts settles over the valley and PM2.5 readings run many times the WHO guideline. Add the cold and the short daylight, and outdoor time is genuinely uncomfortable. A high-grade mask and serious cold-weather gear are essential.
Ger camps are closed, the countryside is locked in deep cold, and there's no festival draw (Tsagaan Sar lands later, in Jan-Feb). December suits only those determined to see winter Mongolia. For the overwhelming majority of visitors, this is the month to avoid — the steppe, the gers, and clean air that make Mongolia special are all out of reach.
What to Wear & What to Pack
Deep midwinter — highs around -13°C, nights near -23°C. Full expedition cold-weather kit: heavy down parka, thermal base layers, insulated boots, hat, balaclava, lined gloves, hand warmers. Severe coal smog hangs over the city; an N95/FFP2 mask is strongly advised.
Packing Checklist
Seasonal Weather Overview
Spring (Mar·Apr·May)
7.7°C
-5°C
4.3/mo
Summer (Jun·Jul·Aug)
22.3°C
10.7°C
11.3/mo
Autumn (Sep·Oct·Nov)
6.3°C
-5.7°C
4.7/mo
Winter (Dec·Jan·Feb)
Current-13.3°C
-23.7°C
2/mo
Ulaanbaatar Monthly Weather Comparison
| Month | High | Low | Rain | Sun | Humid | UV | Crowd | Price |
|---|---|---|---|---|---|---|---|---|
| -16° | -26° | 2d·2mm | 5.5h | 70% | 1 | Quiet | Low season | |
| -11° | -22° | 2d·2mm | 7h | 68% | 2 | Quiet | Low season | |
| -1° | -13° | 3d·3mm | 8h | 55% | 3 | Quiet | Low season | |
| 8° | -4° | 4d·7mm | 8.5h | 45% | 4 | Quiet | Low season | |
| 16° | 2° | 6d·16mm | 9.5h | 45% | 6 | Moderate | Shoulder | |
| June (Best) | 21° | 8° | 9d·40mm | 10h | 50% | 7 | Busy | Peak |
| July (Best) | 24° | 13° | 12d·65mm | 9.5h | 55% | 8 | Very busy | Peak |
| August (Best) | 22° | 11° | 13d·70mm | 9h | 58% | 7 | Busy | Peak |
| 16° | 4° | 7d·23mm | 9h | 50% | 5 | Moderate | Shoulder | |
| 7° | -5° | 4d·6mm | 7.5h | 50% | 3 | Quiet | Low season | |
| -4° | -16° | 3d·4mm | 6h | 60% | 2 | Quiet | Low season | |
| -13° | -23° | 2d·2mm | 5h | 68% | 1 | Quiet | Low season |
View Other Months
Ulaanbaatar December Hotel Picks
Frequently Asked Questions
Is December a good time to visit Ulaanbaatar?
Ulaanbaatar in December is low. Tourist crowds are quiet and flight/hotel prices are low season.
What's the average temperature in Ulaanbaatar in December?
Ulaanbaatar December averages a high of -13°C and a low of -23°C.
Does it rain much in Ulaanbaatar in December?
Ulaanbaatar December averages 2mm of rainfall over about 2 rainy days.
What should I wear in Ulaanbaatar in December?
Deep midwinter — highs around -13°C, nights near -23°C. Full expedition cold-weather kit: heavy down parka, thermal base layers, insulated boots, hat, balaclava, lined gloves, hand warmers. Severe coal smog hangs over the city; an N95/FFP2 mask is strongly advised.
What time are sunrise and sunset in Ulaanbaatar in December?
Ulaanbaatar December sunrise is 08:30 and sunset is 17:00, with 8h 30min of daylight.
What's the air quality like in Ulaanbaatar in December?
Ulaanbaatar December air quality (AQI) averages 180, rated Very poor. PM2.5 averages 125μg/m³.
What activities are recommended in Ulaanbaatar in December?
In December, Ulaanbaatar is great for Indoor museums and monasteries, Short bundled-up sightseeing, Gandan Monastery morning chanting.
Is December peak season in Ulaanbaatar?
Ulaanbaatar December crowds are quiet and prices are low season. You can travel relatively comfortably without long queues.
Best Months to Visit Ulaanbaatar
View Other Months
Planning a December trip to Ulaanbaatar?
You've checked the weather — next come the budget and the route.
Why you can trust weather guide
Based in Chiang Mai for 8+ years, with 30+ countries visited across Southeast Asia, Japan, and Europe. Every detail in this guide is primary-source verified as of April 2026, with prices auto-refreshed via live exchange rate APIs. This isn't AI-generated boilerplate — it's written from the perspective of someone who has actually been there.