TEHRAN – Precipitation in the first month of the spring have contributed to somehow compensating lack of rainfall; currently, the recorded average rainfall is seven percent above the normal figure, the head of the Meteorological Organization has said.

Rainfalls in spring have significantly increased. Compared to the last year, the amount of rainfall has doubled in most areas located in northwest and west of the country, IRIB quoted Ahad Vazifeh as saying.

Overall, the country has received 13 mm more rain in comparison to the long-term period of 30-year, the distribution of precipitations have been unequal, though, Vazifeh noted.

Despite light snowfall in winter, low temperaturealong with abundant rainfall has increased the amount of snow in Alborz and Zagros heights, as well asthe amount of water saved in dams.

Precipitation in the last month of the winter and the first two weeks of the spring was unprecedented in some provinces; in Ilam province, the received rainfall was the highest amount recorded over the past 76 years. The rainfall has been above normal in South Khorasan, Kerman, Hormozgan, south of Fars, and Bushehr provinces, he added.

In Tehran province, the lack of rainfall has dropped from -55 percent to -35 percent.

Rainfalls are forecast to restart in the second month of the spring, particularly in western half of the country. 

As Iran has entered El Niño phase, particularly in spring and summer, precipitation is forecast to be low in southeast of the country in summer, but normal in fall, Vazifeh highlighted.

Currently, El Niño, and La Niña phases are in neutral conditions, that is the difference between the temperature of the water in the surface of Pacific Ocean and 200 meters below the surface of the ocean, in central and eastern parts, is less than 0.5 degrees cooler compared to normal situation which indicates neutral condition, he added. 

However, based on simulated models, the temperature of water at the surface of the ocean is predicted to get more than 0.5 degrees warmer, and enter El Niño Southern Oscillation phase, ISNA quoted Vazifeh as saying.

The situation is not expected to affect summer much as summers are mostly dry in the country; rainfalls in southern half of Sistan-Baluchestan, east of Hormozgan, and south of Kerman will be less than normal.

Precipitation in fall will be influenced by El Niño and are projected to be normal, unlike last year in which rainfall dropped significantly, the official further noted.

Referring to the provinces that have received less-than-normal rainfall, the official said precipitation in Alborz province and Tehran province has been less than normal.

'El Niño' or “the boy” is widely used to describe the warming of sea surface temperature that occurs every few years, typically concentrated in the central-east equatorial Pacific.

'La Niña' or "the girl" is the term adopted for the opposite side of the fluctuation, which sees episodes of cooler than average sea surface temperature in the equatorial Pacific.