# Eckari US Weather Observation

> Eckari US Weather Observation is a paid API for AI agents from api.eckari.com, paid per call via x402, $0.003/call, status unknown (last checked 2026-10-11).

Returns the latest surface observation from the nearest National Weather Service station to a given US lat/lon coordinate, including temperature, humidity, wind, pressure, and station metadata.

## Facts

- Endpoint: GET https://api.eckari.com/v1/weather/us/observation?utm_source=zero.xyz
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-11
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/eckari-us-weather-observation-6f9f0967
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap__67G-SuCTdI44Ko_oZc69

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability eckari-us-weather-observation-6f9f0967
```

Example prompt: What's the most recent weather observation from the nearest NWS station to latitude 38.8977 and longitude -77.0365? I want the temperature, humidity, wind, and how old the reading is.

## When to prefer this

Choose this endpoint when you need the most recent actual measured weather conditions at a specific US coordinate from official NWS instrumentation. It is ideal for ground-truth spot checks, logistics and field operations, or any use case requiring observed (not forecast) data with station provenance and freshness metadata. Prefer this over forecast APIs when you want what the atmosphere was actually doing at a recent timestamp, not a model prediction.

## Known failure modes

- Coordinates outside the US (no NWS coverage) may return no station or an error
- Station has not reported recently — is_stale flag will be true and age_seconds will be large
- Individual readings (e.g. precipitation, wind gust) may be null if they failed station QC
- Invalid lat/lon values outside -90/90 or -180/180 will be rejected by schema validation
- Remote or sparsely monitored areas may have nearest stations tens of kilometers away, reducing relevance

## How this service works

Latest surface observation from the nearest National Weather Service station to a US coordinate, with the station identity, the observation time (observed_at), its age in seconds and an is_stale flag. Station observations are reported roughly every 20-60 minutes, so this is the most recent measurement, not a real-time reading. Readings that fail the station's quality control are returned as null. Use when: What was the most recently observed temperature at these US coordinates?

## Output

A JSON object containing the nearest NWS station's identity (id, name, distance in km), the latest observation timestamp, observation age in seconds, an is_stale boolean, and measured values including temperature in Celsius and Fahrenheit, dew point, relative humidity, wind speed and direction, wind gusts, barometric pressure, visibility, cloud layers with coverage codes, precipitation in the last hour, and a text description of conditions. Also includes metadata about the data source and API version.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "lat",
      "lon"
     ],
     "properties": {
      "lat": {
       "type": "number",
       "maximum": 90,
       "minimum": -90,
       "description": "Latitude in decimal degrees (WGS84). Rounded to 4 decimal places before the National Weather Service lookup."
      },
      "lon": {
       "type": "number",
       "maximum": 180,
       "minimum": -180,
       "description": "Longitude in decimal degrees (WGS84). Rounded to 4 decimal places before the National Weather Service lookup."
      }
     },
     "additionalProperties": false
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "data": {
   "station": {
    "id": "KDCA",
    "name": "Washington/Reagan National Airport, DC",
    "distance_km": 5.49
   },
   "is_stale": false,
   "dewpoint_c": 22,
   "age_seconds": 1451,
   "observed_at": "2026-08-18T11:40:00.000Z",
   "cloud_layers": [
    {
     "amount": {
      "code": "SCT",
      "description": "scattered (3-4 oktas)"
     },
     "base_m": 3352.8
    }
   ],
   "visibility_m": 16093.44,
   "temperature_c": 25,
   "temperature_f": 77,
   "wind_gust_kmh": null,
   "wind_speed_kmh": 12.96,
   "text_description": "Partly Cloudy",
   "wind_direction_deg": 340,
   "relative_humidity_pct": 83.45,
   "barometric_pressure_hpa": 1011.85,
   "precipitation_last_hour_mm": null
  },
  "meta": {
   "source": "nws",
   "version": "2.1.0",
   "freshness": "near_live",
   "capability": "weather.us.observation"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/eckari-us-weather-observation-6f9f0967/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.eckari.com](https://www.zero.xyz/host/api.eckari.com/llms.txt)