Climate and Average Weather Year Round in Nā’īn Iran

In Nā’īn, the summers are hot, arid, and clear and the winters are very cold, snowy, and mostly clear. Over the course of the year, the temperature typically varies from 26°F to 96°F and is rarely below 19°F or above 102°F.

Based on the beach/pool score, the best time of year to visit Nā’īn for hot-weather activities is from late May to early September.

The hot season lasts for 3.8 months, from May 23 to September 17, with an average daily high temperature above 87°F. The hottest month of the year in Nā’īn is July, with an average high of 96°F and low of 69°F.

The cold season lasts for 3.2 months, from November 22 to February 29, with an average daily high temperature below 59°F. The coldest month of the year in Nā’īn is January, with an average low of 27°F and high of 50°F.

In Nā’īn, the average percentage of the sky covered by clouds experiences significant seasonal variation over the course of the year.

The clearer part of the year in Nā’īn begins around May 21 and lasts for 4.9 months, ending around October 18.

The clearest month of the year in Nā’īn is August, during which on average the sky is clear, mostly clear, or partly cloudy 99% of the time.

The cloudier part of the year begins around October 18 and lasts for 7.1 months, ending around May 21.

The cloudiest month of the year in Nā’īn is April, during which on average the sky is overcast or mostly cloudy 34% of the time.

Nā’īn does not experience significant seasonal variation in the frequency of wet days (i.e., those with greater than 0.04 inches of liquid or liquid-equivalent precipitation). The frequency ranges from 1% to 9%, with an average value of 4%.

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 Nā’īn is March, with an average of 2.3 days. Based on this categorization, the most common form of precipitation throughout the year is rain alone, with a peak probability of 9% on March 20.

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. Nā’īn experiences some seasonal variation in monthly rainfall.

Rain falls throughout the year in Nā’īn. The month with the most rain in Nā’īn is March, with an average rainfall of 0.4 inches.

The month with the least rain in Nā’īn is June, with an average rainfall of 0.1 inches.

The length of the day in Nā’īn varies significantly over the course of the year. In 2024, the shortest day is December 21, with 9 hours, 59 minutes of daylight; the longest day is June 21, with 14 hours, 19 minutes of daylight.

The earliest sunrise is at 4:48 AM on June 11, and the latest sunrise is 2 hours, 12 minutes later at 7:01 AM on January 9. The earliest sunset is at 4:50 PM on December 4, and the latest sunset is 2 hours, 19 minutes later at 7:09 PM on June 29.

Daylight saving time (DST) is not observed in Nā’īn 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 Nā’īn, 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 Nā’īn experiences significant seasonal variation over the course of the year.

The windier part of the year lasts for 3.0 months, from May 28 to August 28, with average wind speeds of more than 8.7 miles per hour. The windiest month of the year in Nā’īn is July, with an average hourly wind speed of 10.3 miles per hour.

The calmer time of year lasts for 9.0 months, from August 28 to May 28. The calmest month of the year in Nā’īn is October, with an average hourly wind speed of 7.0 miles per hour.

The predominant average hourly wind direction in Nā’īn varies throughout the year.

The wind is most often from the east for 5.0 months, from May 19 to October 18, with a peak percentage of 67% on July 9. The wind is most often from the west for 7.0 months, from October 18 to May 19, with a peak percentage of 55% on January 1.

To characterize how pleasant the weather is in Nā’īn 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 times of year to visit Nā’īn for general outdoor tourist activities are from early May to early June and from late August to mid October, with a peak score in the third week of September.

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 Nā’īn for hot-weather activities is from late May to early September, with a peak score in the third week of June.

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 Nā’īn typically lasts for 7.9 months (241 days), from around March 19 to around November 15, rarely starting before February 29 or after April 6, and rarely ending before October 28 or after December 2.

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 Nā’īn should appear around March 5, only rarely appearing before February 19 or after March 21.

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 3.5 months, from May 9 to August 26, with an average daily incident shortwave energy per square meter above 7.6 kWh. The brightest month of the year in Nā’īn is June, with an average of 8.6 kWh.

The darker period of the year lasts for 3.2 months, from November 2 to February 9, with an average daily incident shortwave energy per square meter below 4.4 kWh. The darkest month of the year in Nā’īn is December, with an average of 3.4 kWh.

For the purposes of this report, the geographical coordinates of Nā’īn are 32.860 deg latitude, 53.087 deg longitude, and 5,131 ft elevation.

The topography within 2 miles of Nā’īn contains only modest variations in elevation, with a maximum elevation change of 295 feet and an average elevation above sea level of 5,122 feet. Within 10 miles contains only modest variations in elevation (2,123 feet). Within 50 miles contains large variations in elevation (7,841 feet).

The area within 2 miles of Nā’īn is covered by bare soil (46%), shrubs (24%), and cropland (15%), within 10 miles by bare soil (70%) and shrubs (15%), and within 50 miles by bare soil (59%) and shrubs (27%).