Sea-surface temperatures continue to run slightly above average across much of the Equatorial Pacific Ocean. This indicates that the present El Nino phase is persisting. The latest long-range climate models continue to suggest that this current El Nino will remain in place through the rest of the summer and possibly into the upcoming fall season. With that being said, the temperature outlook for July was largely based on El Nino effects during the summer across much of the United States.
Slightly above normal temperatures are forecast across portions of the Pacific Northwest, Great Basin, southern Rockies, and Desert Southwest. A monthly surplus of cooling degree days of between 30 and 60 is projected across the regions of the country. Monthly energy costs with respect to cooling will also likely be at least slightly higher than average.
In contrast, temperatures are projected to average slightly below normal across parts of the north-central Plains, upper Midwest, and Missouri Valley with a monthly deficit of cooling degree days of between 30 and 60 expected.
It should be noted that the NAO (North Atlantic Oscillation) is currently negative and if it remains negative into much of June, this could lead to periods of cooler temperatures across parts of the Northeast and Mid-Atlantic during July as well. For now, much of the southern and eastern United States is forecast to see temperatures average closer to normal during the middle of summer.