get_forecast
Retrieve weather forecasts for US locations by providing latitude and longitude coordinates.
Instructions
Get weather forecast for a location using NWS (US only).
Args:
latitude: Latitude of the location
longitude: Longitude of the locationInput Schema
TableJSON Schema
| Name | Required | Description | Default |
|---|---|---|---|
| latitude | Yes | ||
| longitude | Yes |
Output Schema
TableJSON Schema
| Name | Required | Description | Default |
|---|---|---|---|
| result | Yes |
Implementation Reference
- weather.py:194-229 (handler)The main execution logic for the 'get_forecast' tool. This async function is decorated with @mcp.tool(), which also serves as registration. It fetches the forecast grid point data from NWS API, retrieves the detailed forecast, and formats the next 5 periods into a string response.
@mcp.tool() async def get_forecast(latitude: float, longitude: float) -> str: """Get weather forecast for a location using NWS (US only). Args: latitude: Latitude of the location longitude: Longitude of the location """ print(f"get_forecast called with lat: {latitude}, lon: {longitude}", file=sys.stderr) # First get the forecast grid endpoint points_url = f"{NWS_API_BASE}/points/{latitude},{longitude}" points_data = await make_nws_request(points_url) if not points_data: return "Unable to fetch forecast data for this location." # Get the forecast URL from the points response forecast_url = points_data["properties"]["forecast"] forecast_data = await make_nws_request(forecast_url) if not forecast_data: return "Unable to fetch detailed forecast." # Format the periods into a readable forecast periods = forecast_data["properties"]["periods"] forecasts = [] for period in periods[:5]: # Only show next 5 periods forecast = f""" {period['name']}: Temperature: {period['temperature']}°{period['temperatureUnit']} Wind: {period['windSpeed']} {period['windDirection']} Forecast: {period['detailedForecast']} """ forecasts.append(forecast) return "\n---\n".join(forecasts) - weather.py:195-201 (schema)Input/output schema defined by function signature (latitude: float, longitude: float) -> str and docstring describing parameters.
async def get_forecast(latitude: float, longitude: float) -> str: """Get weather forecast for a location using NWS (US only). Args: latitude: Latitude of the location longitude: Longitude of the location """ - weather.py:24-38 (helper)Supporting utility function used by get_forecast to make authenticated HTTP requests to the NWS API endpoints.
async def make_nws_request(url: str) -> dict[str, Any] | None: """Make a request to the NWS API with proper error handling.""" headers = { "User-Agent": USER_AGENT, "Accept": "application/geo+json" } async with httpx.AsyncClient() as client: try: response = await client.get(url, headers=headers, timeout=30.0) response.raise_for_status() return response.json() except Exception as e: print(f"NWS API error: {e}", file=sys.stderr) return None