Atlanta could top 95 degrees on Wednesday. New York City is forecast to hit 93 by Thursday. Boston, where the average high in late May hovers near 70, may see three consecutive days at or above 90. From Georgia to New England, an unusually powerful ridge of high pressure is locking in a stretch of heat that federal forecasters are calling an early-season heat wave, and it is arriving just as drought conditions across the eastern United States continue to worsen.
The Weather Prediction Center’s extended forecast discussion flags the May 19 through 23 window as the core of the event, driven by a ridge that acts like a lid over the eastern half of the country. That dome of sinking air blocks cooler systems from pushing in and allows heat to build day after day, a pattern more common in July than in mid-May.
City-by-city breakdown
In Atlanta, where average highs for this time of year run in the low 80s, afternoon temperatures are expected to push well into the 90s for several days running. The city sits near the center of the ridge, and with limited cloud cover in the forecast, heat indices could climb into the upper 90s during peak afternoon hours. The NWS forecast office in Peachtree City, Georgia, has noted the potential for near-record warmth on at least one or two days this week, though whether daily records actually fall will depend on exactly how the ridge positions itself.
New York City faces a similar surge. The NWS office in Upton, New York, projects highs in the low-to-mid 90s for the metro area by midweek. Urban heat island effects will keep overnight lows uncomfortably warm, potentially staying above 70 degrees in Manhattan and the inner boroughs. That lack of nighttime relief is what turns a hot day into a dangerous one, particularly for older residents and people in apartments without air conditioning…