Each month, ISciences reports on significant weather events occurring throughout the world and analyze how accurately our Water Security Indicator Model (WSIM) predicted them. In this series, we highlight the most severe global weather events which occurred during the month of April, and discuss the extent of their impact on the affected regions.

Exceptional deficits will remain in northwestern China, while regions of the Yangtze River Basin will observe an expansion of exceptional deficits across the region. 

Extreme to exceptional surpluses in India will resolve, leaving moderate surpluses in central and eastern portions of the country. Deficits are expected to spread in portions of Afghanistan, Pakistan, and northern India. 

Extreme to exceptional surpluses in Maritime Southeast Asia will diminish, though some regions will observe continuing severe to extreme surpluses. Isolated regions in Mainland Southeast Asia will observe exceptional deficits. 

Widespread surpluses in southwestern Russia will mostly diminish. Exceptional deficits are expected in portions of the Urals, European Russia, northern coastal Russia, and in regions east of Lake Baikal. 

Severe to exceptional deficits along the southern coast of Australia will dissipate, though some will continue in Victoria and New Zealand. Severe to exceptional surpluses will continue in Queensland. 

Surpluses of varying intensity will spread further throughout regions of the Sahel, and in southern Africa. Exceptional deficits will remain in northern Africa and central Africa, as well as along the Gulf of Guinea. 

Widespread exceptional deficits will diminish in portions of Brazil, the Southern Cone, and Bolivarian Nations, though some regions of northern, central, eastern, and southern Brazil will observe continued anomalies. Surpluses are expected to arise in portions of the Bolivarian Nations and the Amazon Rainforest. 

Exceptional deficits will persist in regions of the Levant, as well as other Middle Eastern countries, including Iran, Turkey, and Iraq. 

Severe to exceptional deficits will continue in several eastern European countries. Severe to exceptional surplus is anticipated in portions of southern and northern Europe and the Iberian Peninsula. 

Exceptional deficits in northwestern and eastern coastal Mexico will dissipate, but remain in portions of central and southern Mexico. Widespread transitional conditions will resolve in central to southern Mexico and Central America, though some surpluses will continue in Central America. 

Exceptional deficits will continue in several provinces. Northern portions of Nunavut will observe surpluses of varying intensity. 

Exceptional deficits will diminish in portions of the Southwest, but persist in several states within the region. Exceptional deficits are also expected in pockets of Texas and the Midwest, as well as the Carolinas. Alaska will observe continued surpluses. 

The forecast for April 2025 expects significant water deficits for the 12-month period of January 2025 through December 2025 in the southwestern United States, eastern Europe, Mexico, central and northern Africa, central and northern South America, and Central Asia. Areas expected to experience surplus include central and southern Africa, northeastern Australia, and portions of the Amazon rainforest.

In this new series, we examine recent prolonged drought in the Yangtze River Basin, its impact on the affected regions, and the historical accuracy of the Water Security Indicator Model (WSIM) forecasts in East Asia.

Exceptional deficits will spread throughout the Russian Plain, northern coastal Russia, and regions near Lake Baikal. Surpluses are expected in some portions of northern Russia and north-central Kazakhstan. 

Exceptional deficits will continue in northwestern and southeastern China.

Widespread exceptional deficits in the Middle East will downgrade in size, but remain in portions of the Levant, the Arabian Peninsula, and Iran.  

Severe to exceptional deficits will occur throughout most of eastern Europe. Severe to exceptional surpluses in western Europe are expected to dissipate.

While most extreme to exceptional surpluses in Maritime Southeast Asia will resolve, regions of Indonesia and the Philippines will observe surpluses of varying intensity. Moderate to extreme deficits are expected in regions of Sumatra, as well as northern Laos and Vietnam.