Historical humidity data is useful for applications including product storage, agriculture, building operations, human comfort, manufacturing, and weather analysis.
Visual Crossing provides historical, current, and forecast relative humidity through the Visual Crossing Weather Data tools and the Visual Crossing Weather API.
If you do not already have an account, you can sign up for Visual Crossing Weather.
Historical availability varies by location, date, weather element, and source. For current coverage information, see the Visual Crossing Weather Data Availability Guide.
What humidity measures are available?
The primary humidity field is:
humidity
This represents relative humidity as a percentage.
Relative humidity describes the amount of water vapor currently in the air compared with the maximum amount the air could hold at the same temperature.
For example:
humidity = 50
means the air contains approximately 50% of the moisture required for saturation at the current temperature.
Because warmer air can hold more water vapor than colder air, the same relative-humidity percentage can represent different actual amounts of atmospheric moisture at different temperatures.
For this reason, relative humidity is often most useful when interpreted together with:
temp
dew
What is dew point?
The:
dew
field represents dew-point temperature.
Dew point is the temperature to which the air would need to cool for saturation to occur.
Unlike relative humidity, dew point is less directly affected by changes in air temperature and can therefore be useful for comparing atmospheric moisture between different times or locations.
For example:
temp = 85°F
humidity = 65%
dew = 72°F
indicates warm air with a relatively high moisture content.
A lower dew point generally indicates drier air.
Relative humidity versus dew point
Relative humidity and dew point both describe atmospheric moisture, but they answer different questions.
humidity describes how close the air is to saturation at the current temperature.
dew describes the temperature at which saturation would occur and is useful as an indicator of the actual moisture content of the air.
Because relative humidity changes as temperature changes, dew point can sometimes provide a more useful comparison across different times of day or locations.
For many analyses, it is useful to retrieve both.
How does humidity affect feels-like temperature?
Humidity can significantly affect how hot weather feels.
During hot and humid conditions, the Visual Crossing:
feelslike
field reflects heat-index effects.
For example:
temp = 94°F
humidity = 65%
feelslike = 105°F
indicates that humidity is making the apparent temperature significantly warmer than the measured air temperature.
For apparent-temperature analysis, consider retrieving:
temp
humidity
feelslike
For more information, see Where Can I Find Historical Heat Index and Wind Chill Data?.
What are the units and range for humidity?
Relative humidity is expressed as a percentage.
Typical values range from:
0%
to:
100%
A relative humidity of:
100%
means the air is saturated with water vapor at the current temperature.
Lower values indicate progressively drier air.
Unlike temperature, humidity percentage does not change with unitGroup.
For example:
unitGroup=us
and:
unitGroup=metric
both return relative humidity as a percentage.
How is daily humidity calculated?
For daily weather records:
humidity
represents the mean humidity for the day.
Hourly records provide humidity values at hourly resolution.
This distinction is useful when deciding which resolution to request.
Use daily humidity when you need:
- Long historical datasets
- Monthly or seasonal analysis
- Daily business reporting
- Climate summaries
Use hourly humidity when you need:
- Conditions during specific times
- Indoor/outdoor comfort analysis
- Agricultural or manufacturing applications
- Event analysis
- Detailed heat-index analysis
How can I find historical humidity for a location and date?
The easiest no-code option is the Visual Crossing Weather Query Builder.
Enter a location, choose the historical date or date range, select the weather elements you need, and run the query.
You can then:
- Preview the results in your browser
- Download the data
- Use the results in Excel
- Generate an API request for automation
For most humidity analysis, start with:
datetime
temp
humidity
dew
If apparent temperature is important, also include:
feelslike
Look up humidity by address
Visual Crossing can retrieve humidity using a full or partial address.
For example:
1600 Pennsylvania Avenue NW, Washington, DC
The location is geocoded automatically.
After the request, check:
resolvedAddress
latitude
longitude
to confirm that the intended location was matched.
For details, see How to Look Up Weather by Address.
Look up humidity by latitude and longitude
You can also request humidity using coordinates.
Coordinates use:
latitude,longitude
For example:
38.9697,-77.3850
Using coordinates avoids geocoding ambiguity and can be especially useful for:
- Farms
- Construction sites
- Research locations
- Remote locations
- IoT devices
- Locations without a street address
For more information, see How to Look Up Weather by Latitude and Longitude.
Retrieve historical humidity using the Timeline Weather API
For automated applications, use the Timeline Weather API.
The basic historical request structure is:
/timeline/[location]/[date1]/[date2]
For example:
https://weather.visualcrossing.com/VisualCrossingWebServices/rest/services/timeline/London,UK/2026-07-01/2026-07-07?unitGroup=metric&include=days&elements=datetime,temp,tempmax,tempmin,humidity,dew&key=YOUR_API_KEY
This returns daily weather including:
datetime
temp
tempmax
tempmin
humidity
dew
For complete API details, see the Timeline Weather API documentation.
Retrieve hourly humidity
If you need humidity throughout the day, request:
include=hours
For example:
https://weather.visualcrossing.com/VisualCrossingWebServices/rest/services/timeline/London,UK/2026-07-01?unitGroup=metric&include=hours&elements=datetime,temp,humidity,dew&key=YOUR_API_KEY
Each hourly record can then contain values such as:
{
"datetime": "14:00:00",
"temp": 24.6,
"humidity": 61.2,
"dew": 16.7
}
Hourly data is particularly useful when humidity changes substantially during the day.
Retrieve current humidity
Current conditions can be requested using:
include=current
Current conditions are returned in:
currentConditions
and can include:
temp
humidity
dew
feelslike
For example:
https://weather.visualcrossing.com/VisualCrossingWebServices/rest/services/timeline/London,UK?unitGroup=metric&include=current&elements=datetime,temp,humidity,dew,feelslike&key=YOUR_API_KEY
Current conditions use the most recent suitable observations available for the requested location.
Retrieve forecast humidity
Forecast humidity is available through the same Timeline endpoint.
For example:
https://weather.visualcrossing.com/VisualCrossingWebServices/rest/services/timeline/London,UK?unitGroup=metric&include=days,hours&elements=datetime,temp,humidity,dew,feelslike&key=YOUR_API_KEY
This can be useful for:
- Event planning
- Agriculture
- Building operations
- Manufacturing
- Energy
- Outdoor comfort
- Heat-index monitoring
Humidity and temperature should be analyzed together
Relative humidity should not normally be interpreted without considering temperature.
For example:
temp = 40°F
humidity = 80%
and:
temp = 90°F
humidity = 80%
both have the same relative humidity, but the amount of moisture in the atmosphere and the human impact are very different.
This is why a useful humidity dataset often includes:
temp
humidity
dew
rather than humidity alone.
Humidity can vary through the day
Relative humidity often follows a strong daily cycle.
As temperature rises during the day, relative humidity can decrease even if the actual amount of atmospheric moisture changes very little.
As temperature falls overnight, relative humidity often rises.
For example:
06:00 temp = 60°F humidity = 90%
15:00 temp = 82°F humidity = 48%
does not necessarily mean that most of the moisture disappeared from the air during the day.
The temperature change itself affects relative humidity.
Dew point can help distinguish changes in moisture content from changes caused primarily by temperature.
Humidity and precipitation
High relative humidity does not necessarily mean that precipitation is occurring.
A value such as:
humidity = 95%
means the air is close to saturation at the measured location.
Whether precipitation occurs also depends on atmospheric conditions above the surface and other meteorological processes.
For precipitation analysis, use fields such as:
precip
precipprob
preciptype
as appropriate.
Humidity and cloud cover
Humidity and cloud cover are related but are not interchangeable.
Surface relative humidity describes moisture near the measurement level.
Clouds form where air becomes saturated at altitude.
Therefore, it is possible to have:
- High surface humidity with little cloud cover
- Lower surface humidity with clouds overhead
If cloud conditions matter, request:
cloudcover
separately.
Historical humidity sources
Historical humidity can be derived from available weather observations for the requested location and period.
Visual Crossing historical weather can use multiple source networks rather than relying exclusively on a single nearest station.
Source availability can vary by:
- Location
- Date
- Weather element
- Observation quality
- Station network
Historical humidity for a geographic point may therefore be based on a different set of observations than another weather element such as precipitation or snow.
For more information, see How Historical Weather Data Records Are Created from Local Weather Station Observations.
Humidity in remote locations
Humidity coverage can be more limited in areas with sparse observation networks.
If historical humidity appears unavailable or unusual:
- Verify the location.
- Check nearby stations.
- Review the historical date.
- Compare temperature and dew point.
- Consider whether the station-search area should be expanded.
For more guidance, see Finding Historical Weather Data for Remote Locations.
Daily versus hourly humidity analysis
Choose the resolution based on the question.
Use daily records when asking:
What was the average humidity each day?
Use hourly records when asking:
What was the humidity at 2 PM?
or:
How did humidity change during the event?
For long historical analyses, daily data can reduce the dataset size substantially.
For event or comfort analysis, hourly data is usually more useful.
Example: historical humidity analysis
Suppose you want to analyze summer humidity for a location.
Retrieve:
datetime
temp
humidity
dew
for the desired date range.
You can then calculate:
- Mean daily humidity
- Mean dew point
- Maximum humidity
- Minimum humidity
- Number of high-humidity days
- Relationship between temperature and humidity
For example, you might compare:
daily sales
with:
humidity
temperature
to determine whether hot and humid weather affects business performance.
Example: indoor or storage applications
Humidity can be important for products or materials that respond to atmospheric moisture.
Examples include:
- Food
- Pharmaceuticals
- Paper
- Wood
- Electronics
- Agricultural products
Outdoor weather-station humidity does not necessarily represent indoor humidity directly, but it can provide useful environmental context for:
- HVAC demand
- Ventilation
- Condensation risk
- Product transportation
- Outdoor storage
Example: agriculture
Agricultural applications may analyze:
temp
humidity
dew
precip
windspeed
solarenergy
together.
Humidity can affect:
- Evaporation
- Plant disease risk
- Drying conditions
- Irrigation demand
- Crop development
For this reason, humidity is often more useful as part of a broader agricultural-weather dataset than as an isolated field.
Data quality and recent historical updates
Recent historical humidity can change as additional observations become available or upstream providers issue corrected data.
If you are analyzing very recent weather, repeating the query later may return updated values.
For details, see How Historical Weather Data Is Updated.
Summary
Historical relative humidity is available through the Visual Crossing Weather Data tools and Timeline Weather API using:
humidity
Relative humidity is expressed as a percentage.
For a more complete picture of atmospheric moisture, consider retrieving:
temp
humidity
dew
and, when apparent temperature matters:
feelslike
Use daily weather for long-term summaries and hourly weather when the timing of humidity changes matters.
You can retrieve these values using Visual Crossing Weather Data or the Timeline Weather API.
For current field definitions, see the Weather Data Documentation.
If you have questions about a specific humidity request or dataset, contact Visual Crossing Support.