Sea-surface temperatures continue to be slightly warmer than average throughout much of the Equatorial Pacific Ocean. This indicates that the El Nino phase is persisting. The latest long-range climate models continue to suggest that this El Nino may slowly weaken as we head into the upcoming fall and winter. It should be noted that over the past couple weeks, temperatures have cooled slightly in parts of the Equatorial Pacific.
It is too early to determine if this is the beginning of the weakening trend, but this will be monitored closely over the next month. As for the August temperature outlook, slightly below normal temperatures are forecast across portions of the north-central Plains, Midwest, and western Great Lakes with a monthly deficit of cooling degree days of between 30 and 60 expected. It is possible that parts of the Mid-Atlantic and Northeast could also see slightly cooler conditions, especially if the NAO (North Atlantic Oscillation) continues to be negative. In contrast, temperatures are projected to average slightly above normal throughout parts of the Pacific Northwest, Great Basin, Desert Southwest, and perhaps the Southeast. A surplus of monthly cooling degree days of between 20 and 60 is forecast. Energy costs with respect to cooling will also likely be slightly higher than normal across these regions of the U.S.