Question about how to get StationId for lat/lng

[KCRotaryUSA]

I'm calling https://api.weather.gov/stations/KRCM/observations/latest to get the current temp for Kearney, MO. If I didn't know the StationId for a particular lat/lng or City/State, what call(s) can I make get get the StationId? Maybe there is a better call to get the current temp for a lat/lng?

[netbymatt]

This is a multi-step process. You first need the latitude and longitude of the location you're looking to find the observations for. This is outside of the scope of the API but can be accomplished through a "geocoding" service if you're looking to automate the process. Once you have the latitude and Longitude (Kearney, MO used in the examples below):

1. Make a call to the points endpoint with the latitude and longitude https://api.weather.gov/points/39.3528,-94.3711
2. It will respond with links to several other pages with actual weather and forecast data:

{
    "@context": [
        "https://geojson.org/geojson-ld/geojson-context.jsonld",
        {
            "@version": "1.1",
            "wx": "https://api.weather.gov/ontology#",
            "s": "https://schema.org/",
            "geo": "http://www.opengis.net/ont/geosparql#",
            "unit": "http://codes.wmo.int/common/unit/",
            "@vocab": "https://api.weather.gov/ontology#",
            "geometry": {
                "@id": "s:GeoCoordinates",
                "@type": "geo:wktLiteral"
            },
            "city": "s:addressLocality",
            "state": "s:addressRegion",
            "distance": {
                "@id": "s:Distance",
                "@type": "s:QuantitativeValue"
            },
            "bearing": {
                "@type": "s:QuantitativeValue"
            },
            "value": {
                "@id": "s:value"
            },
            "unitCode": {
                "@id": "s:unitCode",
                "@type": "@id"
            },
            "forecastOffice": {
                "@type": "@id"
            },
            "forecastGridData": {
                "@type": "@id"
            },
            "publicZone": {
                "@type": "@id"
            },
            "county": {
                "@type": "@id"
            }
        }
    ],
    "id": "https://api.weather.gov/points/39.3528,-94.3711",
    "type": "Feature",
    "geometry": {
        "type": "Point",
        "coordinates": [
            -94.371099999999998,
            39.352800000000002
        ]
    },
    "properties": {
        "@id": "https://api.weather.gov/points/39.3528,-94.3711",
        "@type": "wx:Point",
        "cwa": "EAX",
        "forecastOffice": "https://api.weather.gov/offices/EAX",
        "gridId": "EAX",
        "gridX": 50,
        "gridY": 61,
        "forecast": "https://api.weather.gov/gridpoints/EAX/50,61/forecast",
        "forecastHourly": "https://api.weather.gov/gridpoints/EAX/50,61/forecast/hourly",
        "forecastGridData": "https://api.weather.gov/gridpoints/EAX/50,61",
        "observationStations": "https://api.weather.gov/gridpoints/EAX/50,61/stations",
        "relativeLocation": {
            "type": "Feature",
            "geometry": {
                "type": "Point",
                "coordinates": [
                    -94.358580000000003,
                    39.355111000000001
                ]
            },
            "properties": {
                "city": "Kearney",
                "state": "MO",
                "distance": {
                    "unitCode": "wmoUnit:m",
                    "value": 1106.7270043128001
                },
                "bearing": {
                    "unitCode": "wmoUnit:degree_(angle)",
                    "value": 256
                }
            }
        },
        "forecastZone": "https://api.weather.gov/zones/forecast/MOZ029",
        "county": "https://api.weather.gov/zones/county/MOC047",
        "fireWeatherZone": "https://api.weather.gov/zones/fire/MOZ029",
        "timeZone": "America/Chicago",
        "radarStation": "KEAX"
    }
}

3. You're interested in properties.observationStations
4. Call the observationStations endpoint https://api.weather.gov/gridpoints/EAX/50,61/stations
5. In the features section of the response you'll receive an array of stations with the first element in the array being the closest. Here's an excerpt.

{
...,
"features": [
        {
            "id": "https://api.weather.gov/stations/KGPH",
            "type": "Feature",
            "geometry": {
                "type": "Point",
                "coordinates": [
                    -94.309600000000003,
                    39.332500000000003
                ]
            },
            "properties": {
                "@id": "https://api.weather.gov/stations/KGPH",
                "@type": "wx:ObservationStation",
                "elevation": {
                    "unitCode": "wmoUnit:m",
                    "value": 236.8296
                },
                "stationIdentifier": "KGPH",
                "name": "Mosby Midwest National Air Center Airport",
                "timeZone": "America/Chicago",
                "forecast": "https://api.weather.gov/zones/forecast/MOZ029",
                "county": "https://api.weather.gov/zones/county/MOC047",
                "fireWeatherZone": "https://api.weather.gov/zones/fire/MOZ029"
            }
        },
...]

6. Use the id provided in the response and add observations/latest endpoint to the end of the url.

An alternative method if you know the WFO office ID you could directly call https://api.weather.gov/offices/{officeId} (EAX for your location) and view the list of approvedObservationStations in the response and pick among them.

[KCRotaryUSA]

Thanks so much. I didn't know the first element in the array meant it was the closest.

[StephenClouse]

Yes, the station list is sorted by distance. I'll make that more clear in the documentation.