On July 27-28, 2024, the territory of the RA was in the zone of influence of the cold atmospheric front passing through the southern edges of the Azorean anticyclone. Due to the influence of the Caucasus Mountains, the cold atmospheric front invaded from the east and the west, due to which rain and thunder were observed throughout the republic and heavy rains in Lori, Tavush, Gegharkunik, Aragatsotn and Kotayk mountainous regions.
Thus, the amount of precipitation in Dilijan was 17,2 mm on July 27, 36,8 mm on July 28, and 34,1 mm was observed only on the night of July 28. In Ijevan, the amount of precipitation was 6,4 mm on July 26, 26 mm on the 27th, and 26,6 mm on the 28th, of which 19,8 mm was observed on the night of the 28th. In Chambarak, the total amount of precipitation on July 27-28 was 77,2 mm, which was 148% of the monthly norm.
As a result, due to the fact that the precipitation was continuous and quite heavy, in the conditions of saturation of the soil with moisture, it led to a rather large surface flow and an increase in water discharges in the rivers.
In particular, a significant increase of water was registered on July 28, when the observed discharges were several times higher than the discharges observed the previous day, the water discharge at Dilijan hydrological observation point of Aghstev River increased from 3,51 m3/s observed at 08:00 on July 27 reached to 28,3 m3/s at 08:00 on July 28, at Ijevan observation point from 7,90 m3/s observed at 08:00 on July 27 reached to 45,8 m3/s at 08:00 on July 28, and at 20:00 to 86,0 m3/s, at Getik-Gosh observation point from 4,12 m3/s observed at 08:00 on July 27 reached to 13,1 m3/s at 08:00 on July 28, and reached to 23,2 m3/s on the morning of the 29th.
During the period 1935-2023, the maximum drainage observed in July at Aghstev-Ijevan hydrological observation point was 107 m3/s which was observed on July 20, 1960. The observed discharge of 86,0 m3/s in 2024 was the second highest historical discharge observed in July for Ijevan hydrological observation point.