Weather Forecast for September in Armenia

Yerevan City
The average monthly air temperature is expected to be +22…+23°C, which is 1-2 degrees higher than the multi-year average value. On certain days, the air temperature may rise during the day to +35…+36°C, with a decrease in temperature at night to +10…+12°C during the second half of the month (historical minimum observed +1…+3°C, maximum +38…+40°C). Monthly precipitation is expected to be close to normal (the norm is 9mm).

The end of summer, according to climatic characterization, is considered to be the time when the daily average air temperature drops below 15°C. In the republic, this transition occurs over three months - from the beginning of July (in high mountainous areas) to the third decade of October (in the Ararat Valley, lowland areas of Syunik and Tavush). Thus, in warm regions, summer weather conditions continue in September, while in mountainous regions, autumn begins.

In September, the average monthly air temperature for the territory of the republic is expected to be +13°C. The absolute maximum temperature in the Ararat Plain and extreme southeast may still reach +35…+40°C, in pre-mountain regions - +33…+38°C, in mountainous regions - +30…+31°C. The first frost is mostly observed in mountainous areas at the end of September; however, in some years (1997), it can be seen even in the first half of the month.

September in Yerevan is considered the most favorable month of the year, with average daily temperatures during the first decade being +22…+23°C, +20°C in the second, and +18…+19°C in the third. Precipitation across the republic is unevenly distributed, with an average of 33mm observed; in the Ararat Plain, Vayots Dzor, and Syunik Valleys - 6-10mm, in Lori - 50-60mm, in the foothills of Syunik - 60-65mm.

According to multi-year data, there have been 12 years where no precipitation was recorded in Yerevan during September, and there was a year (1932) when precipitation reached 86mm, exceeding the norm by nine times. A particularly rainy year was also September 2009, when precipitation in Yerevan amounted to 70mm, exceeding the norm by seven times. The maximum precipitation recorded in Tashir was 218mm, while the minimum was 5mm, which is less than 12 times the norm (1950).

The number of days with precipitation is also unevenly distributed - on average 12 days in Lori, up to 4 days in the Ararat Plain. In high mountainous areas and Gegharkunik, snow cover may appear in the third decade of the month. Thunderstorm activity weakens, averaging 3-6 days, although in some years in the northern half it can be observed for 10-20 days. Hail is rarely observed.

Frequent fog is noted in Syunik, particularly in foothill areas for 6-11 days, and in mountainous regions for 14-19 days. Despite a slight increase in the recurrence of westerly winds in September, their speed does not significantly change.