Tehran – Numerical weather forecast modeling predicts that fall precipitation is expected to be lower than normal, but is expected to exceed normal in winter.
The current water fiscal year began on September 23rd, with rainfall falling in the northern part of the country. An average of 0.5 mm of rain has been recorded nationwide since the start of autumn until September 26th. He said it increased by 19.3% compared to the long-term amount of 0.4 mm.
During the same period, the average temperature was about 1.3°C lower than the long-term average. Only in Sistan-Baluchestan, Kerman and Hormozgan provinces, temperatures were above long-term averages, officials said.
Despite increased rainfall in early autumn, precipitation is expected to be below normal in most areas. Additionally, rainfall is likely to start later than normal, making it about 10 to 15 days behind, Vazifeh said.
From October 7th to November 6th, temperatures will be normal in the eastern half of the country and in the south coastal areas, and in other regions, they will usually be above 0.5-1°C.
From mid-November to mid-December, average temperatures are predicted to be normal in the eastern strip, northern strip and states within the desert plains. It will be above 1-2°C, respectively, and above 0.5-1°C, respectively, in the west and southwest, and other regions.
Numerical modelling shows that rainfall can be nearly normal in late autumn and winter. Winters account for the majority of rainfall, especially in the southern part of the country, officials said.
In past Iranian years (March 2023 – March 2024), precipitation was usually 50-75% lower in the southern part of the country, he added.
Officials went on to say that the country has experienced a series of droughts over the past five years. The previous water year (September 22, 2024 – September 22, 2025) was one of Iran’s exceptional drought years, as rainfall in autumn, winter and spring was significantly reduced. It ended with a precipitation of 142.3 mm, showing a 39.4% decrease compared to the long-term figure of 234.9 mm.
During the last month of summer, 4.1 mm of rainfall was registered nationwide, a 2.5% decrease compared to the long-term figure of 4.2 mm.
Throughout the summer, recorded rainfall reached 8 mm, a 27.9% decrease compared to the long-term figure of 11.1 mm.
Official statistics show that groundwater levels and dam storage have declined significantly, with more water stress in densely populated areas being more experienced than ever, threatening water safety, increasing the likelihood of land subsidence, and increasing drought.
Iran is facing an unprecedented water crisis that threatens not only the agricultural sector but also regional stability and global food markets.
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