Extreme drought now affects 44% of Puerto Rico, according to the U.S. Drought Monitor, with three-quarters of the island experiencing at least moderate drought conditions by August 25, 2026. Many areas have received less than 20% of their usual rainfall, leading to water shortages, rationing, and significant crop losses. Puerto Rico typically enters its wet season in May, but 2026 has seen a severe and rapidly spreading drought. By late August, rainfall remained scarce across much of the U.S. territory, allowing drought conditions to expand quickly. The situation has become serious enough to trigger both local and federal disaster declarations. Puerto Rico's governor declared a state of emergency in late July, and the U.S. government issued a drought disaster declaration covering more than two dozen cities and towns in late August. The map showing the severity and geographic extent of the drought was created by the U.S. Drought Monitor, a collaboration involving the National Drought Mitigation Center at the University of Nebraska-Lincoln, the U.S. Department of Agriculture (USDA), the National Oceanic and Atmospheric Administration, and NASA. NASA has supported the U.S. Drought Monitor for years with Earth observations and scientific expertise. In 2026, two NASA scientists joined the team responsible for producing the weekly drought assessments. David Mocko, a senior research scientist at NASA's Goddard Space Flight Center, noted that the effects of the unusually hot and dry conditions were visible across multiple types of satellite and ground-based data used by the U.S. Drought Monitor. According to the assessment, extreme drought zones (dark orange) in the eastern and southwestern parts of the main island had expanded during the previous week, covering 44% of the territory. This change happened quickly—just three months earlier, no part of Puerto Rico was classified as being in drought, and less than 20% of the territory was considered abnormally dry. From mid-May through mid-July, most of Puerto Rico received less than 60% of its normal precipitation, according to the National Integrated Drought Information System (NIDIS). Southern and southwestern areas were even drier, receiving less than 20% of normal rainfall. This translated to a rainfall deficit of 3 to 6 inches (76 to 152 millimeters). High temperatures worsened the drying, with San Juan experiencing one of its warmest Julys on record. River levels also fell sharply, with streamflow reaching record lows in waterways including the Rio Fajardo in northeastern Puerto Rico. The strain on water supplies has affected residents, farmers, and ranchers across Puerto Rico. Water rationing has been in effect in several municipalities since early August. Observers have also pointed to infrastructure issues as a factor worsening the shortages. The drought has also created serious challenges for agriculture. For farmers, dry soils have disrupted the growth of fruit and cacao trees, as well as banana and coffee plants, contributing to crop losses. Ranchers, meanwhile, are seeing their hay supplies dwindle. U.S. Drought Monitor maps have been published since 1999 and are used by federal, state, local, and tribal officials to guide drought response decisions. The USDA, for example, relies on the maps as part of a "fast track" process for issuing disaster designations, which can help direct emergency assistance and other resources to affected communities.