The best way to find information about high/low humidity levels for your area is to contact your local weather station (likely the closest airport).
For yearly average humidity data, for selected U.S. cities, humidity information can be found from the National Oceanic and Atmospheric Administration’s (NOAA) National Climatic Data Center. This resource is better than other online resources as it is based on long-term, historic averages and is more accurate than looking at a single year.
To use the NOAA humidity data note, it is for selected cities; therefore, use the data from the city nearest your location to determine high/low humidity levels. The M and A in the chart refer to "morning" and "afternoon."
