Climate and monthly weather forecast
Ulaanbaatar, Mongolia

Recognized officially under the Köppen climate classification as a BSk type, Ulaanbaatar, the heart of Mongolia, pulsates under a mid-latitude steppe climate. Its geographical location, nestled in the inland valleys, translates to discernible variations in weather conditions throughout the year.

The Ulaanbaatar weather script sees temperatures morph from a frigid negative of 25.9°C (78.6°F) in the peak winter months to a warm positive of 24.5°C (76.1°F) in the height of summer. This translates to a spectrum of over 50 degrees difference across the year. Humidity reflects a similar oscillation undergoing a shift from 78% in the drier winter season to approximately 50% in the peak summer months. A distinct pattern emerges with daylight duration as well, witnessing an increase from 8.9 hours in the colder months to 16 hours during the warmer summer season.

Rainfall paints a vibrant canvas with significant fluctuations - dry spells are punctuated by a scanty 2mm (0.08") in the initial year months escalating to territory of 70mm (2.76") during the summer zenith. While November to April is characterized by almost negligible rainfall, a surge is noticed from May onwards culminating in July and August. The shift from a frosty landscape to a rain-drenched one is rather precipitous with snowfall days dropping from 10 days in the winter months to nearly nil in May onward.

Reflecting this climatic volatility, sunshine hours travel from lows of 5 hours during the harsh winter to a high of 9.7 hours at summer's bloom. UV index also displays a dynamic range - a low of 1 during the winter months moving towards an 8 during the peak of summer.

Ulaanbaatar presents its best face to the world between May and September. Over these months, the temperature climbs steadily from 9.7°C (49.5°F) to 24.5°C (76.1°F), providing a respite from the biting cold witnessed in most of the year. The relative humidity hovers around a comfortable 50%, creating an environment conducive for outdoor activities. These months also mark the peak of daylight hours, stretching from 15.2 hours to 16 hours per day, allowing visitors to explore the treasures of Ulaanbaatar under the pleasant Mongolian sun.

The period from December to February is perhaps the most challenging in Ulaanbaatar due to harsh climatic conditions. During these months, the mercury plummets from negative 13.5°C (56.3°F) to negative 25.9°C (78.6°F). Relatively high humidity of around 78% compounds the cold severity. Sunshine hours shrink to 5 per day, resulting in shorter days and long nights. Alongside the chill, snowfall increases to 10 days, adding more to the harsh winters.

Between March and May, Ulaanbaatar starts to break the winter shackles. The temperature creeps from the negative territory into the positive, ranging from negative 0.7°C (33.3°F) to 17.8°C (64°F) high and negative 13.6°C (56.5°F) to 3.3°C (37.9°F) low. Humidity dips from 61% to 46% complementing the warm wind. Daylight rises dramatically from 11.9 hours to 15.2 hours and the sunshine duration per day also sees a significant surge from 8.6 hours to 9.7 hours. This spontaneous burst of light marks the onset of Ulaanbaatar’s bloom.

June to August is when summer reigns supreme. Throughout this period, the temperatures stabilize around a high of 22.5°C (72.5°F) to 24.5°C (76.1°F) and a low of 9.6°C (49.3°F) to 12.9°C (55.2°F). Humidity experiences a slight increase ranging from 54% to 63%. The most remarkable upturn comes in the form of rain, with average rainfall increasing from 46mm (1.81") to 70mm (2.76"). The number of daylight hours peak at 16 hours during these months, granting visitors plenty of sunshine.

Autumn, September to November, witnesses falling temperatures dropping from 16.7°C (62.1°F) to negative 5°C (41°F) between high and low. Nonetheless, it is during this season that sunshine hours are still reasonably high, fluctuating around 7.3 - 8.2 hours per day. Average rainfall recedes from 27mm (1.06") in September to 6mm (0.24") by November, and November typically marks the resurgence of snowfalls, growing from 2 to 8 days per month.

The onset of November marks the beginning of winter carrying on until February with average high temperatures plummeting to negative 13.5°C (56.3°F) by December and frigid lows of negative 22.9°C (73.2°F). During this period, relative humidity peaks at around 78%, contributing to the biting cold. Add to that the decline in daylight hours to a lean 8.5 hours by December, and the onset of heavy snowfall, the winter months prove a daunting prospect for visitors.

Ulaanbaatar ushers in the New Year with low temperatures, ranging from -25.9°C (-14.6°F) to -15.6°C (3.9°F), reflecting a bracing winter ambience. A blanket of snow covers the city as snowfall occupies eight days of the month. Weather in January »

A shift is noted in Ulaanbaatar's weather pattern as February rolls in. Yet, despite a slight increase, temperatures are still nestled well below freezing. The mercury hovers between -22.2°C (-8°F) and -9.6°C (14.7°F), making it slightly warmer than January. Weather in February »

The arrival of March signals the advent of milder conditions in Ulaanbaatar. With the harsh winter slowly retreating, the city transitions from intense cold to a more tolerable cold. The temperature gauge moves up, demonstrating a considerable leap as it ranges from -13.6°C (7.5°F) to -0.7°C (30.7°F). Weather in March »

Transitioning from frigid temperatures, April ushers in springtime with noticeable warmth in Ulaanbaatar. A discernible rise in temperatures imbues the city with a relatively warmer atmosphere, making outdoor pursuits more enjoyable. Weather in April »

Warm weather takes hold in Ulaanbaatar during May, welcoming the pleasant vibes of late spring. Milder temperatures and extended daylight hours characterise this period, fostering ideal conditions for sightseeing and exploration. Be prepared for a drastic escalation in temperatures, ranging from 3.3°C (37.9°F) to 17.8°C (64°F), which invites the onset of balmy weather. Weather in May »

June brings the comfort of summer to Ulaanbaatar, exuding a congenial atmosphere perfect for outdoor activities. With lengthened daylight hours, city dwellers and tourists alike can enjoy extended outings. The city endures the year's highest temperature, showcasing a range from 9.6°C (49.3°F) to 22.5°C (72.5°F). Weather in June »

Basking in the full glory of summer, July boasts superb weather conditions in Ulaanbaatar. The long daylight hours set the perfect ambiance for visiting tourist hotspots and recreational parks. An appreciable fluctuation in the mercury level reaching from 12.9°C (55.2°F) to 24.5°C (76.1°F) validates July as the hottest month. Weather in July »

August holds onto the summer warmth but prepares to say farewell to the season in Ulaanbaatar. Pleasant temperatures persist, but the tell-tale signs of the approaching autumn are subtly visible. The temperature scales marginally downwards as it stays between 10.6°C (51.1°F) and 22.3°C (72.1°F). Weather in August »

September ushers in autumn in Ulaanbaatar, manifesting a perceptible cooling trend. While the daily sunshine duration barely changes, the shorter daylight hours herald the incoming fall season. Settling between 3.6°C (38.5°F) and 16.7°C (62.1°F), temperatures begin to feel the chill of autumn. Weather in September »

The autumn chill deepens in October in Ulaanbaatar. The city starts preparing for the winter as temperatures continually drop, and the daylight hours shorten. From a cool 3.6°C (38.5°F), it dips to a much lower -4.8°C (23.4°F), enhancing the cold sensation. Weather in October »

November in Ulaanbaatar witnesses the city delicately balancing on the precipice of winter. The seemingly abrupt transition to winter becomes more pronounced amid falling temperatures and reduced daylight hours. Marking the commencement of winter, temperatures oscillate between a cold -15.7°C (3.7°F) and a chillier -5°C (23°F). Weather in November »

December marks the peak of winter in Ulaanbaatar with temperatures consistently below freezing. Biting winds whip through the city streets, and snowflakes dance in the air to paint a wintry landscape. The December chill is intense with temperatures ranging from -22.9°C (-9.2°F) to -13.5°C (7.7°F). Weather in December »