Where summers are muggy: the dew point of U.S. cities: PlainClimate analysis of NOAA data, published October 8, 2026
59 of 138 large U.S. cities with NOAA hourly normals average a summer dew point of 65°F or more, the level most people feel as muggy; Brownsville, TX is the muggiest (74.7°F) and Reno, NV the driest (36.9°F). 13 stay under 50°F.
Every large city with hourly normals, muggiest first
Summer (June-August) dew point and 3 p.m. relative humidity, 1991-2020 hourly normals
The mean of NOAA's 1991-2020 hourly normal dew point over every hour of June, July and August at each place's official station, for Census places of 100,000 or more people whose station has hourly normals (NOAA keeps them only for first-order stations). The 3 p.m. relative humidity is shown beside it.
What it cannot tell you
Dew point measures the moisture in the air; relative humidity depends on the temperature as well, so a hot afternoon can show a low humidity with a high dew point. Comfort thresholds (under 55°F dry, 55-65°F noticeable, over 65°F muggy) are common guidance, not a NOAA standard.