Weather Forecast API: Coordinates to forecast in one call, with high, low, peak precipitation — NWS

Coordinates to forecast in one call, with high, low, peak precipitation probability and wet-period count computed across the window. Free, no key.

Free — no key, no signup, rate-limited to 60 calls per minute per client.

How do you call it?

GET /v1/weather/forecast — product id weather_forecast. Over MCP, call answerpool_get with product_id=weather_forecast.

curl "https://answerpool.io/v1/weather/forecast?latitude=38.8894&longitude=-77.0352"

Live call: https://answerpool.io/v1/weather/forecast?latitude=38.8894&longitude=-77.0352 · JSON sample: /v1/samples/weather_forecast

What does the answer look like?

A representative response, the same static sample served at /v1/samples/weather_forecast.

periods

{
 "as_of": "2026-09-03T16:00:00Z",
 "grid": "LWX/97,71",
 "city": "Washington",
 "state": "DC",
 "periods_returned": 2,
 "high_f": 88.0,
 "low_f": 71.0,
 "max_precip_probability_pct": 60.0,
 "periods_with_precip_50pct_plus": 1,
 "periods": [
  {
   "name": "Today",
   "start": "2026-09-03T12:00:00-04:00",
   "is_daytime": true,
   "temperature_f": 88.0,
   "wind": "5 to 10 mph SW",
   "precipitation_probability_pct": 60.0,
   "short_forecast": "Chance Showers And Thunderstorms"
  }
 ],
 "note": "Highs, lows and precipitation aggregates are computed by AnswerPool across the returned periods; the per-period values are as issued by the forecast office.",
 "source": "NOAA National Weather Service (api.weather.gov)",
 "refresh_after": "2026-09-17T11:15:00.000Z"
}

How fresh is it, and where does the data come from?

The fastest source behind this answer can change every 15 minutes, so every response carries a refresh_after timestamp — right now it would be 2026-09-17T11:15:00.000Z. Schedule the next call on that value rather than on a guess.

• NOAA National Weather Service (US federal public domain) — upstream: https://api.weather.gov

Method version 0.1.0 · serving cache 1 day · every response carries a result_id you can resolve at /v1/provenance.

When should you use it?

You need a point forecast plus its summary numbers.

What you skip building

• the NWS points-then-gridpoints two-step
• min/max passes over forecast periods

When should you not use it?

Active warnings — /v1/weather/alerts.

Where else can you find this?

• Catalog entry (JSON, free)
• OpenAPI schema — input and output types, prices, the 402 flow
• llms.txt — every product in one plain-text document