Assessment of NMME Skill over Southwest Asia and Horn of Africa

The 14th Weather Squadron (14WS) is the Department of Defense (DoD)’s organization responsible for delivering climate information and services to DoD entities. One of the most recent efforts at 14WS to deliver relevant decision-grade climate information to DoD mission planners has been to introduce long-range forecast capability based on the North American Multi-Model Ensemble (NMME). The National Centers for Environmental Prediction (NCEP) Climate Prediction Center (CPC) currently uses NMME as one of many inputs into their monthly long-range forecast production process. However, whereas CPC’s long-range forecast efforts are focused primarily on the Contiguous United States (CONUS), the DoD operates in many locations throughout the globe outside of CONUS. Recently, extreme drought in Somalia and exacerbated tensions in Syria have caused the focus of DoD military and humanitarian mission planning to shift to the Horn of Africa (HoA) and further remain in Southwest Asia (SWA). The skill of NMME’s temperature and precipitation anomaly forecasts is assessed at all available lead times (1 – 7 months) and over the area including Afghanistan, Iran, Iraq, Syria, Pakistan, Jordan, the Arabian Peninsula, Djibouti, Somalia, Ethiopia, and Kenya. The operational forecasts from August 2011 – June 2017 will be considered. Ranked Probability Skill Score (RPSS) is used to assess the skill of the adjusted probabilistic forecasts, and a skill score based on the root mean squared error (RMSE_SS) is used for the deterministic anomaly forecasts.