TEHRAN –Since the beginning of the current water year (September 22) till November 23, rainfall across the country amounted to 25.4 mm, indicating a 20-percent decrease compared to 31.7 mm recorded in the same period last year.

A total of 20 provinces of the country have received less rainfall compared to the same period last year, IRNA reported.

Khuzestan province recording 9.4 mm of rainfall has experienced an 88 percent decline in precipitations, compared to 76.3 mm recorded in the same period last year.

However, rainfall in Razavi Khorasan province has increased by 146 percent. The amount of received rainfall totalled 20.7 mm, the figure was 8.4 mm last year.

According to numerical weather prediction modelling, Metrological Organization has forecasted the fall weather to be warmer than normal with low precipitation.

The warm and cold phases of the Pacific Ocean affect the weather, the transition from El Niño (warm phase) to La Niña (cold phase) is going on slowly, ISNA quoted Ahad Vazifeh, an official with Metrological Organization, as saying.

Most models indicate weak La Niña conditions from November to February. In this condition, indicators that change in the short term such as the North Atlantic Oscillation (Nao), and Madden-Julian Oscillation (MJO) become more effective and impact, he further noted.

Over 250mm rain in previous water year

The previous water year (September 22, 2023 – September 22, 2024) came to an end with receiving 252.7 mm of precipitation, showing a 19 percent increase compared to the year before.

The low precipitations at the beginning of the previous water year were worrisome, but the volume of precipitations improved with the passage of time.

Due to successive years of drought, the increase in rainfall amounts did not compensate water deficit in the country, some provinces are suffering from water shortage, IRNA reported.

A total of 10 provinces received less than normal rainfall.

According to the latest reports, the total amount of recorded rainfall in the previous water year (ended on September 23) amounted to 252.7 mm, which signifies a 19 percent increase compared to 212.9 mm rain received in the water year before (September 2022 –September 2023).

Compared to the long-term figure, 248.7, it shows a two percent increase.

MT/MG