Drought Update for Puerto Rico and the U.S. Virgin Islands

Overview

Drought conditions changed little across Puerto Rico in the past two months, and drought remains and continues to fluctuate in the U.S. Virgin Islands. The upcoming wet months and tropical season are expected to improve drought conditions. Drought conditions have remained fairly constant since June, with 8% of Puerto Rico currently in moderate drought (D1) at this time. A small area of severe drought (D2) remains on the northwest coast. In the U.S. Virgin Islands (USVI), conditions continue to fluctuate, with moderate drought (D1) in Saint John, and extreme drought (D3) in Saint Thomas and Saint Croix. This is a 1-category improvement for St. Croix since early June, but a 1-category degradation for St. Thomas. Dry and hot conditions have impacted farming and ranching in the USVI.

Looking Ahead: September, October, and November are the 3 wettest consecutive months of the year for both Puerto Rico and the USVI. Precipitation during these 3 months will be critical for breaking the persistent drought in the USVI. Average rainfall for these 3 months ranges from about 15 inches on St. Croix to 20 inches for St. Thomas. This will be greatly influenced by tropical systems; the updated NOAA Atlantic Basin Tropical Cyclone Outlook for 2023 now calls for above-normal tropical cyclone activity being the most likely outcome. Based mainly on this, the new Seasonal Drought Outlook from the National Weather Service's Climate Prediction Center calls for drought to improve across both Puerto Rico and USVI by the end of November. This represents the first-ever issuance of a Seasonal Drought Outlook for the USVI.

Current and Future Drought Conditions

Drought Conditions

• Puerto Rico: Around 9% of Puerto Rico is currently considered dry or in drought according to the U.S. Drought Monitor, with nearly 7% categorized as Moderate Drought (D1) and nearly 2% categorized as Severe Drought (D2).
• U.S. Virgin Islands: According to the U.S. Drought Monitor, Moderate Drought (D1) is observed across Saint John, and Extreme Drought (D3) across both Saint Thomas and Saint Croix. 

Sector Impacts

Agricultural Conditions 

• Puerto Rico: Livestock and dairy farmers in the coastal Southwest region of Puerto Rico experienced periods of rain from mid-July until today. The rains have been short-lived, followed by high temperatures (sometimes 98 degrees) causing great evapotranspiration and affecting the growth of pastures. In the coastal south region (Juana Díaz and Coamo municipality), pastures have maintained green on a weekly basis, and no overall abnormally dry conditions have been noticed in the past few weeks. 
  • Dry spells affected farmers in the central region of Puerto Rico (Naranjito, Comerío, Cidra, and Barranquitas) during some weeks in June. Fruit trees grown in high tunnels experienced stress by lack of water. Plantains and root crops were less affected by dry conditions because farmers incorporated cover crops and maintained weeds on site, which helped retain soil humidity. Even though dry conditions were noted, it has not been worse than other years. Rain episodes occurred throughout mid-July and August, and some farmers reported erosion and landslides in neighboring lands.  
  • Farmers in the West-Central mountainous region of Puerto Rico (Utuado and Maricao municipality) experienced long periods without rain between June and mid-July. Coffee production was affected even though it is mostly produced in shade. Producers experienced deficiency in coffee shrubs, premature flowering and maturing, and fruit drying before harvest. 
  • Farmers in the northern region of Puerto Rico (Manatí municipality) reported that June has been the driest and most difficult month to work with by far. Production of greens such as bok choy, arugula, and cress has decreased or lost quality due to heat and hydric stress. They also experienced premature flowering and harvesting periods due to stress. 
  • All farmers indicated that these past few months, high temperatures made labor and practices more difficult than in other years. To avoid exhaustion and heat stress, farmers limit their work hours to mornings and evenings for both themselves and their crops and animals.
• St. Thomas: Farmers on St.Thomas report that ponds are slowly filling due to sporadic rains. Winds, often above 20 mph, reduced soil moisture. Due to almost-daily concerns about heat (90°F or above) and humidity at or above 75%, and current drought conditions, farmers are planning and preparing irrigation and water efficiency tools to better manage water as part of a longer-term mitigation and conservation plan. Many are considering the use of permaculture and/or tree planting to create shade areas to aid them with soil moisture retention. Specialty and row crop farmers are working to manage water usage by installing gravity-fed irrigation tools and are moving to more drought-tolerant crops to keep production up while still conserving water. Many are still not planting due to drought conditions and are working on land management practices to aid them during non-drought periods. Livestock farmers are rotating livestock.
• St. John: Row and specialty crop farmers on St. John report that recent rains are helping alleviate the dry conditions. However, high winds and excessive heat are reducing soil moisture retention and negatively impacting farmers. Most are currently focusing on microgreens, fruit trees, and quick crops to keep production up and are rotating crops. Most are also preparing land for the wet season, when they hope to increase production and make up for sales that were reduced during the dry season and this current drought.
• St. Croix: Farmers report that recent intermittent showers are not penetrating the soil due to evaporation from high winds. Livestock farmers are working to plan for feed shortages later this summer due to a lack of grass during the hotter months. The Virgin Islands Department of Agriculture (VIDA) is currently buying and storing hay. Growers reported losses of more than 203 livestock along with 20 horses since April.  Poultry farmers report that egg production has been reduced by up to 50% due to the heat, and they are concerned because there is little to no Ginney grass and chickens are not eating grain. Extreme heat is increasing water usage for farmers and causing lower egg production during this molting season. Farmers who have poultry, including both broilers and/or egg production, have smaller numbers because they must collect water in containers or use cistern water. Orders of up to 500 chicks have been placed, and farmers are waiting for new arrivals to prepare for production during the cooler climate. VIDA on St. Croix reported in June that they provided more than 1,291,180  gallons of water to farmers in June, 1,020,050 gallons in July, and 903,930 in August. Ranchers are looking for drought mitigation strategies to plan for vegetation distress and land management due to longer-term droughts in recent years. 
• Assistance for USVI farmers and ranchers: According to the U.S. Department of Agriculture, St. Croix and St. Thomas already qualified for a 2023 secretarial drought disaster declaration, based on the U.S. Drought Monitor (USDM) depiction.  Similarly, livestock producers in St. Croix and St. Thomas qualified for direct assistance through the USDM-driven Livestock Forage Program.  LFP assistance begins when severe drought (D2) lasts 8 weeks or more, with payments tripling when the extreme drought (D3) threshold is reached and quadrupling upon spending 4 weeks at D3 or attaining exceptional drought (D4).

Rainfall Trends

Heavy rains over the southern coast of Puerto Rico in the past 60 days resulted in the removal of all drought across the southern part of the island. Some lingering rainfall deficits in the northwest coast contributed to continued moderate to severe drought in this area (Figure 2 and Figure 3).

Soil Moisture Conditions in Puerto Rico

The latest soil moisture data from the Puerto Rico Agricultural Water Management (PRAGWATER) indicates dry soil conditions persist across portions of eastern Puerto Rico and areas of the southwest and northwest coast (Figures 4 and 5). 

Streamflow and Reservoir Conditions in Puerto Rico 

The real-time 28-day average streamflow from the U.S. Geological Survey (USGS) river gauge network (Figure 6) indicates that, except for the northwest coast, rivers and stream flows are mostly near-normal across the island. View more information on groundwater levels along the South Coast of Puerto Rico.

Outlooks

Rainfall Outlook

In accordance with the Seasonal Drought Outlook (Figure 1) from the National Weather Service's Climate Prediction Center, the latest North American Multi-Model Ensemble (NMME) shows a strong likelihood of normal to above normal rainfall for the Greater Antilles during the fall (Figure 7).

For More Information

• National Weather Service (NWS) Weather Forecast Office – San Juan: Climate and Drought Information
• NWS Drought Information Statements for Puerto Rico and the U.S. Caribbean
• Drought.gov:
  • Puerto Rico page
  • U.S. Virgin Islands page
• Caribbean Drought Bulletins. Caribbean Regional Climate Center, Caribbean Institute for Meteorology and Hydrology (CIMH), Barbados
• U.S. Department of Agriculture (USDA) Caribbean Climate Hub drought and disaster assistance resources for tropical forestry and agriculture

Prepared By

Odalys Martinez and Emanuel Rodriguez
National Weather Service Weather Forecast Office – San Juan

Héctor J. Jiménez
Office of Climatology, University of Puerto Rico

Meredith Muth
NOAA/National Integrated Drought Information System (NIDIS)

Victor Murphy
National Weather Service Southern Region

Christina Chanes
University of Virgin Islands

Silmarie Crespo Vélez and Nora Álvarez-Berríos
USDA Caribbean Climate Hub, USFS International Institute of Tropical Forestry

Brad Rippey
USDA Office of the Chief Economist

Timothy Dalrymple
USGS Caribbean - Florida Water Science Center (CFWSC)