fourzerotwo-si Us Weather API
US Weather (NWS): US forecasts, hourly forecasts, active weather alerts and station observations from the National Weather Service.
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OpenAPI Specification
openapi: 3.2.0
info:
title: Fourzerotwo Si Us Weather API
version: 1.1.0
contact:
url: https://fourzerotwo.si
description: 'Operations tagged us-weather across 2 of this provider''s published API definitions: openapi.json, fourzerotwo-si-openapi.json. Each path carries the servers of the definition it was published in.'
servers:
- url: https://fourzerotwo.si
tags:
- name: us-weather
description: 'US Weather (NWS): US forecasts, hourly forecasts, active weather alerts and station observations from the National Weather Service.'
paths:
/v1/us-weather/points:
get:
operationId: us_weather__points
summary: 'US Weather (NWS): Point metadata'
description: 'Forecast office, grid and nearby stations for a US lat,lon. Price: $0.001 USDC per call via x402. Free within the daily allowance with a free key.'
tags:
- us-weather
externalDocs:
url: https://fourzerotwo.si/apis/us-weather/points
parameters:
- name: point
in: query
required: true
description: '"lat,lon"'
schema:
type: string
example: 40.7128,-74.006
responses:
'200':
description: The data (paid, or free tier).
content:
application/json: {}
'402':
$ref: '#/components/responses/PaymentRequired'
'400':
$ref: '#/components/responses/Error'
'404':
$ref: '#/components/responses/Error'
'502':
$ref: '#/components/responses/Error'
security:
- {}
- freeKey: []
x-price-usd: '0.001000'
x-free-tier: free
x-mcp-tool: us-weather__points
servers:
- url: https://fourzerotwo.si
/v1/us-weather/forecast:
get:
operationId: us_weather__forecast
summary: 'US Weather (NWS): 7-day forecast'
description: 'Twice-daily forecast periods for a grid square. Price: $0.002 USDC per call via x402. Free within the daily allowance with a free key.'
tags:
- us-weather
externalDocs:
url: https://fourzerotwo.si/apis/us-weather/forecast
parameters:
- name: office
in: query
required: true
description: Forecast office id from the points endpoint
schema:
type: string
example: OKX
- name: x
in: query
required: true
description: Grid X
schema:
type: integer
example: 33
- name: y
in: query
required: true
description: Grid Y
schema:
type: integer
example: 42
responses:
'200':
description: The data (paid, or free tier).
content:
application/json: {}
'402':
$ref: '#/components/responses/PaymentRequired'
'400':
$ref: '#/components/responses/Error'
'404':
$ref: '#/components/responses/Error'
'502':
$ref: '#/components/responses/Error'
security:
- {}
- freeKey: []
x-price-usd: '0.002000'
x-free-tier: free
x-mcp-tool: us-weather__forecast
servers:
- url: https://fourzerotwo.si
/v1/us-weather/forecast-hourly:
get:
operationId: us_weather__forecast_hourly
summary: 'US Weather (NWS): Hourly forecast'
description: 'Hourly forecast for a grid square. Price: $0.002 USDC per call via x402. Free within the daily allowance with a free key.'
tags:
- us-weather
externalDocs:
url: https://fourzerotwo.si/apis/us-weather/forecast-hourly
parameters:
- name: office
in: query
required: true
description: Forecast office id from the points endpoint
schema:
type: string
example: OKX
- name: x
in: query
required: true
description: Grid X
schema:
type: integer
example: 33
- name: y
in: query
required: true
description: Grid Y
schema:
type: integer
example: 42
responses:
'200':
description: The data (paid, or free tier).
content:
application/json: {}
'402':
$ref: '#/components/responses/PaymentRequired'
'400':
$ref: '#/components/responses/Error'
'404':
$ref: '#/components/responses/Error'
'502':
$ref: '#/components/responses/Error'
security:
- {}
- freeKey: []
x-price-usd: '0.002000'
x-free-tier: free
x-mcp-tool: us-weather__forecast-hourly
servers:
- url: https://fourzerotwo.si
/v1/us-weather/alerts-active:
get:
operationId: us_weather__alerts_active
summary: 'US Weather (NWS): Active alerts by state'
description: 'Weather alerts in force for a US state or marine area. Price: $0.002 USDC per call via x402. Free within the daily allowance with a free key.'
tags:
- us-weather
externalDocs:
url: https://fourzerotwo.si/apis/us-weather/alerts-active
parameters:
- name: area
in: query
required: true
description: State code, e.g. CA
schema:
type: string
example: CA
responses:
'200':
description: The data (paid, or free tier).
content:
application/json: {}
'402':
$ref: '#/components/responses/PaymentRequired'
'400':
$ref: '#/components/responses/Error'
'404':
$ref: '#/components/responses/Error'
'502':
$ref: '#/components/responses/Error'
security:
- {}
- freeKey: []
x-price-usd: '0.002000'
x-free-tier: free
x-mcp-tool: us-weather__alerts-active
servers:
- url: https://fourzerotwo.si
/v1/us-weather/alerts-point:
get:
operationId: us_weather__alerts_point
summary: 'US Weather (NWS): Active alerts at a point'
description: 'Weather alerts in force at a lat,lon. Price: $0.002 USDC per call via x402. Free within the daily allowance with a free key.'
tags:
- us-weather
externalDocs:
url: https://fourzerotwo.si/apis/us-weather/alerts-point
parameters:
- name: point
in: query
required: true
description: '"lat,lon"'
schema:
type: string
example: 40.7128,-74.006
responses:
'200':
description: The data (paid, or free tier).
content:
application/json: {}
'402':
$ref: '#/components/responses/PaymentRequired'
'400':
$ref: '#/components/responses/Error'
'404':
$ref: '#/components/responses/Error'
'502':
$ref: '#/components/responses/Error'
security:
- {}
- freeKey: []
x-price-usd: '0.002000'
x-free-tier: free
x-mcp-tool: us-weather__alerts-point
servers:
- url: https://fourzerotwo.si
/v1/us-weather/station-latest:
get:
operationId: us_weather__station_latest
summary: 'US Weather (NWS): Latest observation'
description: 'Latest observed conditions at a weather station. Price: $0.001 USDC per call via x402. Free within the daily allowance with a free key.'
tags:
- us-weather
externalDocs:
url: https://fourzerotwo.si/apis/us-weather/station-latest
parameters:
- name: station
in: query
required: true
description: Station id, e.g. KNYC
schema:
type: string
example: KNYC
responses:
'200':
description: The data (paid, or free tier).
content:
application/json: {}
'402':
$ref: '#/components/responses/PaymentRequired'
'400':
$ref: '#/components/responses/Error'
'404':
$ref: '#/components/responses/Error'
'502':
$ref: '#/components/responses/Error'
security:
- {}
- freeKey: []
x-price-usd: '0.001000'
x-free-tier: free
x-mcp-tool: us-weather__station-latest
servers:
- url: https://fourzerotwo.si
components:
responses:
PaymentRequired:
description: x402 payment required. The body (also base64 in the PAYMENT-REQUIRED header) lists accepted payments.
headers:
PAYMENT-REQUIRED:
schema:
type: string
description: Base64 JSON x402 v2 PaymentRequired
content:
application/json:
schema:
type: object
properties:
x402Version:
type: integer
error:
type: string
accepts:
type: array
items:
type: object
Error:
description: 400 = invalid input, 404 = not found at the source, 502 = the source failed. Never charged.
content:
application/json:
schema:
type: object
properties:
error:
type: string
charged:
type: boolean
securitySchemes:
freeKey:
type: apiKey
in: header
name: X-API-Key
description: Optional free key (fzt_…) for the free tier.
x-refined-from:
- openapi.json
- fourzerotwo-si-openapi.json