The U.S. Month 1-5 Outlook Highlights Hot and Dry Climate West/Central U.S.

Discussion: The Climate Impact Company month 1-5 ahead outlook valid for April to August 2025 is updated. The Q2/2025 outlook is biased very warm to hot across an expanding Southwest U.S. drought (Fig. 1-2). Dry climate extends to the Central U.S. during mid-spring to early summer. The wet bias during Q2 is across the East U.S. Meteorological summer 2024-25 is projected to expand the Southwest heat observed during early warm season to across the entire West U.S. extending to the Great Plains. During summertime, the dry bias is across the Northwest to parts of the Central U.S. while a wet monsoon develops in the Southwest U.S. and the East is biased wetter than normal (Fig. 3-4). PDSI forecasts valid for the end of May and end of July reveal a West and Central U.S. drought risk (Fig. 5-6).

Fig. 1-2: The CIC-CA temperature/precipitation anomaly outlook for APR/MAY/JUN 2025.

Fig. 3-4: The CIC-CA temperature/precipitation anomaly outlook for JUN/JUL/AUG 2025.

Fig. 5-6: The CIC-CA PDSI forecast for end of May and end of July 2025.

Climate discussion: The forecast is based on a constructed analog. The analog is based on initialization of the forecast identifying a large Southwest U.S. drought and (secondarily) a North-central U.S. drought. The ECMWF global SSTA forecast for evolving conditions in the North Pacific and North Atlantic plus ENSO are heavily considered. Included is warming of the western North Atlantic and formation of a strong North Atlantic warm hole (NAWH) south of Greenland. The Gulf of Mexico and Caribbean Sea are warmer than normal. In the North Pacific, expanding and intensifying marine heat waves are likely although not reaching the U.S. West Coast as the new version of the cool phase Pacific decadal oscillation continues. The ENSO forecast is tricky; ECMWF has the warmest SSTA in the eastern equatorial East Pacific of all models.