Climate and Average Weather Year Round in Sayn-Ust Mongolia

In Sayn-Ust, the summers are long and warm, the winters are frigid, and it is dry and partly cloudy year round. Over the course of the year, the temperature typically varies from -5°F to 80°F and is rarely below -15°F or above 89°F.

Based on the tourism score, the best time of year to visit Sayn-Ust for warm-weather activities is from late June to mid August.

The warm season lasts for 3.9 months, from May 16 to September 12, with an average daily high temperature above 67°F. The hottest month of the year in Sayn-Ust is July, with an average high of 79°F and low of 56°F.

The cold season lasts for 3.2 months, from November 21 to February 27, with an average daily high temperature below 27°F. The coldest month of the year in Sayn-Ust is January, with an average low of -4°F and high of 14°F.

In Sayn-Ust, the average percentage of the sky covered by clouds experiences mild seasonal variation over the course of the year.

The clearer part of the year in Sayn-Ust begins around July 24 and lasts for 2.5 months, ending around October 10.

The clearest month of the year in Sayn-Ust is September, during which on average the sky is clear, mostly clear, or partly cloudy 69% of the time.

The cloudier part of the year begins around October 10 and lasts for 9.5 months, ending around July 24.

The cloudiest month of the year in Sayn-Ust is April, during which on average the sky is overcast or mostly cloudy 40% of the time.

A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. The chance of wet days in Sayn-Ust varies throughout the year.

The wetter season lasts 2.9 months, from June 4 to September 2, with a greater than 9% chance of a given day being a wet day. The month with the most wet days in Sayn-Ust is July, with an average of 5.3 days with at least 0.04 inches of precipitation.

The drier season lasts 9.1 months, from September 2 to June 4. The month with the fewest wet days in Sayn-Ust is January, with an average of 0.0 days with at least 0.04 inches of precipitation.

Among wet days, we distinguish between those that experience rain alone, snow alone, or a mixture of the two. The month with the most days of rain alone in Sayn-Ust is July, with an average of 5.3 days. Based on this categorization, the most common form of precipitation throughout the year is rain alone, with a peak probability of 18% on July 4.

Rainfall

To show variation within the months and not just the monthly totals, we show the rainfall accumulated over a sliding 31-day period centered around each day of the year. Sayn-Ust experiences some seasonal variation in monthly rainfall.

The rainy period of the year lasts for 2.3 months, from June 13 to August 22, with a sliding 31-day rainfall of at least 0.5 inches. The month with the most rain in Sayn-Ust is July, with an average rainfall of 0.8 inches.

The rainless period of the year lasts for 9.7 months, from August 22 to June 13. The month with the least rain in Sayn-Ust is January, with an average rainfall of -0.0 inches.

The length of the day in Sayn-Ust varies significantly over the course of the year. In 2024, the shortest day is December 21, with 8 hours, 28 minutes of daylight; the longest day is June 21, with 15 hours, 57 minutes of daylight.

The earliest sunrise is at 4:44 AM on June 16, and the latest sunrise is 3 hours, 45 minutes later at 8:29 AM on January 2. The earliest sunset is at 4:51 PM on December 10, and the latest sunset is 3 hours, 51 minutes later at 8:42 PM on June 25.

Daylight saving time (DST) is not observed in Sayn-Ust during 2024.

The figure below presents a compact representation of key lunar data for 2024. The horizontal axis is the day, the vertical axis is the hour of the day, and the colored areas indicate when the moon is above the horizon. The vertical gray bars (new Moons) and blue bars (full Moons) indicate key Moon phases.

We base the humidity comfort level on the dew point, as it determines whether perspiration will evaporate from the skin, thereby cooling the body. Lower dew points feel drier and higher dew points feel more humid. Unlike temperature, which typically varies significantly between night and day, dew point tends to change more slowly, so while the temperature may drop at night, a muggy day is typically followed by a muggy night.

The perceived humidity level in Sayn-Ust, as measured by the percentage of time in which the humidity comfort level is muggy, oppressive, or miserable, does not vary significantly over the course of the year, remaining a virtually constant 0% throughout.

This section discusses the wide-area hourly average wind vector (speed and direction) at 10 meters above the ground. The wind experienced at any given location is highly dependent on local topography and other factors, and instantaneous wind speed and direction vary more widely than hourly averages.

The average hourly wind speed in Sayn-Ust experiences significant seasonal variation over the course of the year.

The windier part of the year lasts for 3.9 months, from March 17 to July 15, with average wind speeds of more than 7.9 miles per hour. The windiest month of the year in Sayn-Ust is May, with an average hourly wind speed of 9.7 miles per hour.

The calmer time of year lasts for 8.1 months, from July 15 to March 17. The calmest month of the year in Sayn-Ust is January, with an average hourly wind speed of 6.0 miles per hour.

The predominant average hourly wind direction in Sayn-Ust varies throughout the year.

The wind is most often from the north for 8.2 months, from February 10 to October 16, with a peak percentage of 52% on June 17. The wind is most often from the south for 3.8 months, from October 16 to February 10, with a peak percentage of 41% on January 1.

To characterize how pleasant the weather is in Sayn-Ust throughout the year, we compute two travel scores.

The tourism score favors clear, rainless days with perceived temperatures between 65°F and 80°F. Based on this score, the best time of year to visit Sayn-Ust for general outdoor tourist activities is from late June to mid August, with a peak score in the third week of July.

The beach/pool score favors clear, rainless days with perceived temperatures between 75°F and 90°F. Based on this score, the best time of year to visit Sayn-Ust for hot-weather activities is from early July to early August, with a peak score in the third week of July.

Methodology

For each hour between 8:00 AM and 9:00 PM of each day in the analysis period (1980 to 2016), independent scores are computed for perceived temperature, cloud cover, and total precipitation. Those scores are combined into a single hourly composite score, which is then aggregated into days, averaged over all the years in the analysis period, and smoothed.

Our cloud cover score is 10 for fully clear skies, falling linearly to 9 for mostly clear skies, and to 1 for fully overcast skies.

Our precipitation score, which is based on the three-hour precipitation centered on the hour in question, is 10 for no precipitation, falling linearly to 9 for trace precipitation, and to 0 for 0.04 inches of precipitation or more.

Our tourism temperature score is 0 for perceived temperatures below 50°F, rising linearly to 9 for 65°F, to 10 for 75°F, falling linearly to 9 for 80°F, and to 1 for 90°F or hotter.

Our beach/pool temperature score is 0 for perceived temperatures below 65°F, rising linearly to 9 for 75°F, to 10 for 82°F, falling linearly to 9 for 90°F, and to 1 for 100°F or hotter.

Definitions of the growing season vary throughout the world, but for the purposes of this report, we define it as the longest continuous period of non-freezing temperatures (≥ 32°F) in the year (the calendar year in the Northern Hemisphere, or from July 1 until June 30 in the Southern Hemisphere).

The growing season in Sayn-Ust typically lasts for 3.9 months (121 days), from around May 18 to around September 15, rarely starting before April 28 or after June 4, and rarely ending before August 31 or after October 1.

Growing degree days are a measure of yearly heat accumulation used to predict plant and animal development, and defined as the integral of warmth above a base temperature, discarding any excess above a maximum temperature. In this report, we use a base of 50°F and a cap of 86°F.

Based on growing degree days alone, the first spring blooms in Sayn-Ust should appear around May 5, only rarely appearing before April 27 or after May 15.

This section discusses the total daily incident shortwave solar energy reaching the surface of the ground over a wide area, taking full account of seasonal variations in the length of the day, the elevation of the Sun above the horizon, and absorption by clouds and other atmospheric constituents. Shortwave radiation includes visible light and ultraviolet radiation.

The average daily incident shortwave solar energy experiences extreme seasonal variation over the course of the year.

The brighter period of the year lasts for 3.8 months, from April 20 to August 13, with an average daily incident shortwave energy per square meter above 6.4 kWh. The brightest month of the year in Sayn-Ust is June, with an average of 7.5 kWh.

The darker period of the year lasts for 3.3 months, from October 30 to February 9, with an average daily incident shortwave energy per square meter below 2.8 kWh. The darkest month of the year in Sayn-Ust is December, with an average of 1.6 kWh.

For the purposes of this report, the geographical coordinates of Sayn-Ust are 47.357 deg latitude, 94.524 deg longitude, and 4,751 ft elevation.

The topography within 2 miles of Sayn-Ust contains only modest variations in elevation, with a maximum elevation change of 282 feet and an average elevation above sea level of 4,747 feet. Within 10 miles contains only modest variations in elevation (1,765 feet). Within 50 miles contains very significant variations in elevation (5,046 feet).

The area within 2 miles of Sayn-Ust is covered by bare soil (100%), within 10 miles by bare soil (100%), and within 50 miles by bare soil (100%).