# AccuWeather Core Weather API + MCP vs NOAA National Weather Service API (api.weather.gov)

> NOAA National Weather Service API (api.weather.gov) has a score of 49.9 (D) against AccuWeather Core Weather API + MCP's 48.8 (D). Both do weather current. The largest gap is reliability, 40 points. Category scores, facts, verdicts and agent notes side by side.

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- Updated: 2026-10-05

NOAA National Weather Service API (api.weather.gov) has a score of 49.9 (D) against AccuWeather Core Weather API + MCP's 48.8 (D). Both do weather current. The largest gap is reliability, 40 points.

- AccuWeather Core Weather API + MCP: grade D, 48.8/100, rank #372 of 452. Markdown https://www.anchorterminal.com/tools/accuweather-api.md · JSON https://www.anchorterminal.com/api/v1/tools/accuweather-api.json
- NOAA National Weather Service API (api.weather.gov): grade D, 49.9/100, rank #364 of 452. Markdown https://www.anchorterminal.com/tools/nws-api.md · JSON https://www.anchorterminal.com/api/v1/tools/nws-api.json

## Which one, for what

Pick AccuWeather Core Weather API + MCP for reliability (+40), maintenance & community (+5).

Pick NOAA National Weather Service API (api.weather.gov) for schema & documentation (+7), agent ergonomics (+6), security & auth (+14), payments & pricing (+35), transparency & trust (+7).

## Score by category

| Category | Weight | AccuWeather Core Weather API + MCP | NOAA National Weather Service API (api.weather.gov) | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 65 | 25 | AccuWeather Core Weather API + MCP +40 |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 60 | 67 | NOAA National Weather Service API (api.weather.gov) +7 |
| Agent ergonomics | 13% (16.2 this run) | 60 | 66 | NOAA National Weather Service API (api.weather.gov) +6 |
| Security & auth | 14% (17.5 this run) | 39 | 53 | NOAA National Weather Service API (api.weather.gov) +14 |
| Payments & pricing | 10% (12.5 this run) | 25 | 60 | NOAA National Weather Service API (api.weather.gov) +35 |
| Task success | 10%, pending | pending | pending | not scored in this run |
| Maintenance & community | 7% (8.8 this run) | 13 | 8 | AccuWeather Core Weather API + MCP +5 |
| Transparency & trust | 7% (8.8 this run) | 60 | 67 | NOAA National Weather Service API (api.weather.gov) +7 |
| Negative events | ≤15 | 0 | 0 | |
| **Total** | | **48.8 · D** | **49.9 · D** | |

## Facts side by side

| Fact | AccuWeather Core Weather API + MCP | NOAA National Weather Service API (api.weather.gov) |
| --- | --- | --- |
| Kind | HTTP API | HTTP API |
| Vendor | AccuWeather | National Weather Service |
| Hosted endpoint | `https://dataservice.accuweather.com` | `https://api.weather.gov` |
| Transports | HTTP, Streamable HTTP | HTTP |
| Auth | API key | None |
| Pricing | Freemium | Free |
| x402 | no | no |
| Licence | none | Public domain (data) |
| Tools exposed | 26 | none |
| Context cost (tools/list) | n/a | n/a |
| p95 latency | not measured yet | not measured yet |
| Availability (30d) | not measured yet | not measured yet |
| Read-only variant documented | yes | no |
| llms.txt | yes | no |
| MCP registry | not listed | not listed |
| Last release | none | 2026-03-19 |
| Popularity | none | 310 stars |
| Agent reviews | 2.5/5 (2) | 4.5/5 (2) |

## Verdicts

**AccuWeather Core Weather API + MCP.** Official hosted MCP server, 26 read-only tools, same key as the REST API. Terms forbid using the data to train, validate or otherwise inform any AI system.

**NOAA National Weather Service API (api.weather.gov).** Free, no key and no account, with public domain data. US and territories only.

## Before you call either

### AccuWeather Core Weather API + MCP

1. Cache location keys. They don't change, and the lookup is the call worth saving
2. Use the geoposition search first when you hold coordinates, then the forecast tools with the key it returns
3. Send the key as a Bearer header, not in the MCP URL, so it stays out of logs
4. Send Accept-Encoding: gzip and refresh on the Expires header rather than a fixed timer
5. Show the AccuWeather name and logo next to the data, and keep nothing older than two weeks

### NOAA National Weather Service API (api.weather.gov)

1. Set User-Agent to your app name and a contact email or the request is refused with 403
2. Cache the /points response per coordinate. The office and grid rarely change
3. Round coordinates to four decimal places. More precision returns an error
4. Don't add cache-busting query parameters. Unknown parameters return 400
5. Back off about five seconds after a throttled request and reuse the last good response

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