Programmatic Access to AZMet Data with a Web API

The API endpoint to retrieve AZMet 15-minute data is https://api.azmet.arizona.edu/v1/observations/15min/{stationID}/{startDate}/{timeInterval} where parameters enclosed in {} are the following variables:

• {stationID}: a valid AZMet station ID
• {startDate}: the first datetime, inclusive, of data to return
• {timeInterval}: the time duration of data to return

{stationID} A list of valid station IDs is available on the AZMet website for stations currently listed as active. Use of * for this parameter will return, as default, data for all AZMet stations with data given the context of the other two parameters. Also dependent on the other two parameters, returned data when using * may include the Test station, station ID az99, which is adjacent to the Tucson station, station ID az01, and used to test equipment and sensors before operational field deployment.

{startDate} Entries for this parameter are a valid ISO 8601 datetime without a time zone offset and of the form YYYY-MM-DDTHH:MM where:

• YYYY: represents a four-digit year
• MM: represents a two-digit calendar month
• DD: represents a two-digit day of the specified month
• T: for time, a literal that does not change based on the parameter value and marks the start of the time designator
• HH: represents a two-digit hour between 00 and 23
• MM: represents a two-digit minute between 00 and 59

Use of * for this parameter will result in a default datetime for 15-minute data, which for the AZMet API is set to the date and time representing the start of the past 24 hours of 15-minute data, Arizona date and time. Learn more about the ISO 8601 standard.

{timeInterval} Entries for this parameter are a valid ISO 8601 duration of the form PT[h]H where:

• P: for period, a literal that does not change based on the parameter value and indicates what follows is a duration designator
• T: for time, a literal that does not change based on the parameter value and indicates that the value that follows is a duration value for time
• [h]: represents a non-negative integer value of the number of hours
• H: for hour, a literal that does not change based on the parameter value and marks the hour designator that follows the value for the number of hours

Use of * for this parameter defaults to 24 hours of 15-minute data and is equivalent the {timeInterval} parameter being set to PT24H.

Although ISO 8601 durations have a period designator, P, at the start of the duration representation that can precede values for year, month, week, day, minute, and second, the AZMet API conveniently requires only a number-of hours value, [h], in the {timeInterval} parameter. Learn more about the format of this parameter.

Parameters at the end of this API endpoint are not required to retrieve 15-minute data and, if missing, will take default values. Asterisk placeholders can be used to specify defaults for a parameter while defining parameters later in the request URL.

Using Tucson as an example AZMet station, access to 15-minute data over the past 24 hours is through the following URL: https://api.azmet.arizona.edu/v1/observations/15min/az01/*/* 

• The {stationID} parameter is az01 (AZMet station metadata)
• The {startDate} parameter is *, with YYYY-MM-DD and HH:MM automatically set to the date and time representing the start of the past 24 hours of 15-minute data
• The {timeInterval} parameter also is *, with the number of hours, [h], automatically set to 24

The API endpoint to retrieve AZMet hourly data is https://api.azmet.arizona.edu/v1/observations/hourly/{stationID}/(startDate}/timeInterval} where parameters enclosed in {} are the following variables:

• {stationID}: a valid AZMet station ID
• {startDate}: the first datetime, inclusive, of data to return
• {timeInterval}: the time duration of data to return

{stationID} A list of valid station IDs is available on the AZMet website for stations currently listed as active. Use of * for this parameter will return, as default, data for all AZMet stations with data given the context of the other two parameters. Also dependent on the other two parameters, returned data when using * may include the Test station, station ID az99, which is adjacent to the Tucson station, station ID az01, and used to test equipment and sensors before operational field deployment.

{startDate} Entries for this parameter are a valid ISO 8601 datetime without a time zone offset and of the form YYYY-MM-DDTHH:MM where:

• YYYY: represents a four-digit year
• MM: represents a two-digit calendar month
• DD: represents a two-digit day of the specified month
• T: for time, a literal that does not change based on the parameter value and marks the start of the time designator
• HH: represents a two-digit hour between 00 and 23
• MM: represents a two-digit minute between 00 and 59

Use of * for this parameter will result in a default date for hourly data, which for the AZMet API is set to the most recent calendar day with 24 hourly observations, Arizona date and time. Learn more about the ISO 8601 standard.

{timeInterval} Entries for this parameter are a valid ISO 8601 duration of the form PT[h]H where:

• P: for period, a literal that does not change based on the parameter value and indicates what follows is a duration designator
• T: for time, a literal that does not change based on the parameter value and indicates that the value that follows is a duration value for time
• [h]: represents a non-negative integer value of the number of hours
• H: for hour, a literal that does not change based on the parameter value and marks the hour designator that follows the value for the number of hours

Use of * for this parameter defaults to 24 hours of hourly data and is equivalent to the {timeInterval} parameter being set to PT24H

Although ISO 8601 durations have a period designator, P, at the start of the duration representation that can precede values for year, month, week, day, minute, and second, the AZMet API conveniently requires only a number-of-hours value, [h], in the {timeInterval} parameter. Learn more about the format of this parameter.

Parameters at the end of this API endpoint are not required to retrieve hourly data and, if missing, will take default values. Asterisk placeholders can be used to specify defaults for a parameter while defining parameters later in the request URL.

Using January 1, 2020, and Tucson as an example date and AZMet station, access to hourly data on this day is through the following URL: https://api.azmet.arizona.edu/v1/observations/hourly/az01/2020-01-01T00:00/PT24H 

• The {stationID} parameter is az01 (AZMet station metadata)
• The {startDate} parameter is 2020-01-01T00:00, with YYYY-MM-DD set to 2020-01-01 and HH:MM set to 00:00
• The {timeInterval} parameter is PT24H, with the number of hours, [h], set to 24

As the {timeInterval} parameter represents a duration, this example data request returns any hourly data that is recorded at the AZMet Tucson station starting with a timestamp at 00:00 and ending 24 hours later. Since the timestamp for hourly data occurs at the top of every hour, or HH:00, except for midnight, Arizona time, which has a timestamp of 23:59:59, data returned in this example would start with those from the 0100 hour and end with those from the 2400 hour. There is no 0000-hour representation of midnight in data accessed through the AZMet API.

The API endpoint to retrieve AZMet daily data is https://api.azmet.arizona.edu/v1/observations/daily/{stationID}/(startDate}/timeInterval} where parameters enclosed in {} are the following variables:

• {stationID}: a valid AZMet station ID
• {startDate}: the first datetime, inclusive, of data to return
• {timeInterval}: the time duration of data to return

{stationID} A list of valid station IDs is available on the AZMet website for stations currently listed as active. Use of * for this parameter will return, as default, data for all AZMet stations with data given the context of the other two parameters. Also dependent on the other two parameters, returned data when using * may include the Test station, station ID az99, which is adjacent to the Tucson station, station ID az01, and used to test equipment and sensors before operational field deployment.

{startDate} Entries for this parameter are a valid ISO 8601 datetime without a time zone offset and of the form YYYY-MM-DDTHH:MM where:

• YYYY: represents a four-digit year
• MM: represents a two-digit calendar month
• DD: represents a two-digit day of the specified month
• T: for time, a literal that does not change based on the parameter value and marks the start of the time designator
• HH: represents a two-digit hour between 00 and 23
• MM: represents a two-digit minute between 00 and 59

Use of * for this parameter will result in a default date for daily data, which for the AZMet API is set to the most recent calendar day with 24 hours of observations, Arizona date and time. Learn more about the ISO 8601 standard.

{timeInterval} Entries for this parameter are a valid ISO 8601 duration of the form P[d]D where:

• P: for period, a literal that does not change based on the parameter value and indicates what follows is a duration designator
• [d]: represents a non-negative integer value of the number of days beyond the {startDate}
• D: for day, a literal that does not change based on the parameter value and marks the day designator that follows the value for the number of days

Use of * for this parameter defaults to one day of daily data and is equivalent to the {timeInterval} parameter being set to P0D.

Although ISO 8601 durations have a period designator, P, at the start of the duration representation that can precede values for year, month, week, day, minute, and second, the AZMet API conveniently requires only a number-of-days value, [d], in in the {timeInterval} parameter. Learn more about the format of this parameter.

Parameters at the end of this API endpoint are not required to retrieve daily data and, if missing, will take default values. Asterisk placeholders can be used to specify defaults for a parameter while defining parameters later in the request URL.

Using January 1, 2020, and Tucson as an example date and AZMet station, access to daily data on this day is through the following URL: https://api.azmet.arizona.edu/v1/observations/daily/az01/2020-01-01T00:00/P0D  

• The {stationID} parameter is az01 (AZMet station metadata)
• The {startDate} parameter is 2020-01-01T00:00, with YYYY-MM-DD set to 2020-01-01 and HH:MM set to 00:00
• The {timeInterval} parameter is P0D, with the number of days, [d], set to 0

As the {timeInterval} parameter represents a duration, this example data request returns any daily data that is recorded at the AZMet Tucson station starting with a date of 2020-01-01 and ending zero days later, or in other words, that same date. If, for instance, data for the entire month, or 31 days, of January 2020 instead were of interest, one would set [d] to 30.