NOAA Climate Server

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Overview

NOAA Climate Data Online (CDO) API v2 for historical weather observations, plus two separate NCEI bulk-CSV corpora — the Storm Events Database and Billion-Dollar Weather and Climate Disasters. Search locations and stations, fetch historical observations with date-range validation and unit conversion, and query severe-weather events or disaster costs from any MCP client. Runs as a stdio process, a local Streamable HTTP server, or the public hosted endpoint above.

Tools

Tool	Description
noaa_climate_list_datasets	List available CDO datasets with IDs, names, and temporal coverage
noaa_climate_list_data_categories	List data category groups (Temperature, Precipitation, Wind, etc.)
noaa_climate_list_data_types	List specific measurement labels (TMAX, TMIN, PRCP, SNOW, etc.) by dataset or category
noaa_climate_list_location_categories	List the 12 location categories that scope location search
noaa_climate_find_locations	Search geographic locations by category (states, cities, counties, zip codes, climate regions), with an optional name filter
noaa_climate_find_stations	Search weather stations by location, bounding box, dataset, and data type
noaa_climate_get_station	Fetch full metadata for a single station by ID
noaa_climate_fetch_data	Fetch historical observation records for a dataset and date range
noaa_climate_search_storm_events	Search the NCEI Storm Events Database for one year — tornadoes, hail, floods, hurricanes, with damage, casualties, and narratives
noaa_climate_get_billion_dollar_disasters	Query NOAA's Billion-Dollar Weather and Climate Disasters — CPI-adjusted costs and deaths per disaster, or per-year totals by disaster class

Resources

Resource	Description
noaa://datasets	All CDO datasets with IDs and temporal coverage — injectable context for orienting an agent before querying data
noaa://stations/{stationId}	Station metadata by ID — name, coordinates, elevation, and data coverage date range

Capability reference

noaa_climate_list_datasets _tool

• No required parameters — returns all ~11 CDO datasets by default; optional filters by data type, location, station, or date range
• Paginated (limit 1–1000, default 25; offset), sortable by id, name, mindate, maxdate, or datacoverage
• Common IDs: GHCND (daily, 1763–present), GSOM (monthly), GSOY (annual), NORMAL_DLY/MLY/ANN/HLY (1981–2010 normals)

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noaa_climate_list_data_categories _tool

• 42 categories total (Temperature, Precipitation, Wind, Pressure, Sunshine, Sky cover, Weather Type, and more)
• Optional filters by dataset, location, station, or date range; paginated (limit 1–1000, default 25; offset), sortable by id or name
• Use before noaa_climate_list_data_types to narrow by measurement domain

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noaa_climate_list_data_types _tool

• Filter by datasetId (e.g. GHCND) or datacategoryId (e.g. TEMP) — hundreds of types exist across all datasets
• Common GHCND types: TMAX, TMIN, PRCP, SNOW, SNWD, AWND
• Coverage fraction and date range are included only when the upstream record carries them
• Paginated (limit 1–1000, default 25; offset)

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noaa_climate_list_location_categories _tool

• Returns the 12 category IDs noaa_climate_find_locations accepts as locationCategoryId: CITY, ST, CNTY, CNTRY, ZIP, US_TERR, CLIM_REG, CLIM_DIV, HYD_ACC, HYD_CAT, HYD_REG, HYD_SUB
• Sortable by id or name; paginated (limit 1–1000, default 25; offset)
• Pagination and sort only — CDO ignores dataset, location, station, and date filters on this endpoint, so none are offered

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noaa_climate_find_locations _tool

• locationCategoryId scopes the search (e.g. ST returns all 51 states in one call); omit it to return every location type
• nameContains synthesizes the name search CDO lacks by enumerating the category client-side and matching the substring case-insensitively — capped to categories of at most 4,000 locations (every category but ZIP, 30,415); a datasetId/datacategoryId filter can narrow a larger category under that limit
• Returns location IDs used by noaa_climate_find_stations and noaa_climate_fetch_data — FIPS:37, CITY:US530018, ZIP:98101
• Typed failures when nameContains is passed without locationCategoryId, or the resolved category is too large to enumerate
• Paginated (limit 1–1000, default 25; offset); sort alphabetically by name to page through an over-large category instead

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noaa_climate_find_stations _tool

• Filter by locationId, extent (lat/lon bounding box), datasetId, datatypeId (array), and date range
• Returns station IDs, names, coordinates, elevation, and data-coverage dates — station IDs feed noaa_climate_fetch_data as stationId
• Pair datasetId and date range to confirm a returned station actually has data for what you plan to query
• Common station ID formats: GHCND:USW00024233, COOP:010008
• Paginated (limit 1–1000, default 25; offset)

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noaa_climate_get_station _tool

• Single required input: stationId
• Returns name, coordinates, elevation, and full data-coverage date range
• Mirrors the noaa://stations/{stationId} resource as a direct call
• not_found when the ID is well-formed but resolves to nothing

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noaa_climate_fetch_data _tool

• Requires datasetId, startDate, endDate; optional stationId, locationId, datatypeId filters (arrays)
• Date-range cap depends on dataset: GHCND, PRECIP_15, PRECIP_HLY, NORMAL_DLY, NORMAL_HLY, NEXRAD2, NEXRAD3 allow 1 year max; GSOM, GSOY, NORMAL_MLY, NORMAL_ANN allow 10 years max, measured to the end of the calendar month that many years after startDate
• units: "metric" or "standard" is strongly recommended — without it, GHCND values are raw tenths-of-unit integers (e.g. TMAX=256 is 25.6°C)
• For any NORMAL_* dataset, use startDate=2010-01-01 / endDate=2010-12-31 — the fixed API proxy year regardless of which 30-year period is described
• date_range_exceeded reports the exact maxEndDate CDO will accept; an unrecognized datasetId fails validation_error before any network call
• Returns flat { date, datatype, station, value, attributes } tuples plus an effectiveQuery echo of the applied filters

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noaa_climate_search_storm_events _tool

• Separate NCEI bulk-CSV corpus — no token required; year is required (1950 through the current partial year, one file per year)
• Filter by state (the full NCEI name, e.g. "FLORIDA", never a postal code), eventType (matched case-insensitively against the exact NWS label), month, and minDamageInUsd
• Damage arrives as both the raw magnitude-suffixed string ("1.20M") and a parsed dollar amount; an unreported figure is omitted rather than reported as zero, and minDamageInUsd excludes those rows and reports how many it dropped
• limit 1–100 (default 50) with offset; a zero-match response names the event types and states the requested year actually contains
• year_unavailable when NCEI has no file for the year; malformed_export if a downloaded file fails to decompress into the expected table

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noaa_climate_get_billion_dollar_disasters _tool

• Two shapes: individual disasters by default, or summary=true for per-year counts and costs by disaster class plus an "All Disasters" total
• Every cost is normalized to whole US dollars regardless of the unit NCEI declares per export (millions for the per-event file, billions for the national per-year file); the response echoes the source unit as declaredCostUnit
• Filter by startYear/endYear (overlap match), disasterType (one of seven exact NCEI classes), minCostInUsd, and state (two-letter postal code)
• A state scope reports each disaster's national cost, not a state share (costBasis: "national"), and its per-year rows carry a binned costRangeInUsd instead of a point estimate and confidence bands
• Coverage runs 1980 through the last year NCEI has finished assessing (coveredYears), not the current calendar year; limit 1–100 (default 50) with offset

---

noaa://datasets _resource

• All CDO datasets as application/json — IDs, names, temporal coverage
• Equivalent to noaa_climate_list_datasets with no filters and a high limit — injectable, zero-fetch context

---

noaa://stations/{stationId} _resource

• Station metadata by ID — mirrors noaa_climate_get_station
• stationId comes from noaa_climate_find_stations
• not_found when the ID is well-formed but resolves to nothing

Features

Built on @cyanheads/mcp-ts-core: stdio and Streamable HTTP transports, pluggable auth (none / jwt / oauth), swappable storage (in-memory, filesystem, Supabase, Cloudflare KV/R2/D1), structured logging with optional OpenTelemetry tracing.

NOAA-specific:

• Full CDO API v2 coverage — datasets, data categories, data types, locations, stations, and observations — plus two separate NCEI bulk-CSV corpora requiring no token: severe-weather events (Storm Events Database) and billion-dollar disaster costs
• Client-side date-range validation enforced per dataset before hitting the API, reporting the exact upstream limit back to the caller
• Unit normalization via CDO's units parameter avoids raw tenths-of-unit integer confusion
• CDO's own rejection message is recovered and surfaced — an over-long date range, malformed date, missing parameter, or over-large limit reports the reason CDO gave instead of a bare status line
• Billion-Dollar Disasters costs are converted to whole US dollars from whichever unit each NCEI export declares in its own preamble, since the unit differs by export

Agent-friendly output:

• Paginated results across every list and search tool — limit, offset, and total count in every response
• Station, location, and dataset IDs flow naturally between tools — find a location, find stations in it, fetch data from those stations
• Structured error contracts with typed reason codes and recovery hints — agents branch on data, not string parsing
• Damage and cost fields are honest about upstream gaps — an unreported NCEI figure is omitted rather than reported as a confirmed zero

Getting started

Public Hosted Instance

A public instance is available at https://noaa-climate.caseyjhand.com/mcp — no installation required. Point any MCP client at it via Streamable HTTP:

{
  "mcpServers": {
    "noaa-climate-mcp-server": {
      "type": "streamable-http",
      "url": "https://noaa-climate.caseyjhand.com/mcp"
    }
  }
}

Self-Hosted / Local

Add the following to your MCP client configuration file.

{
  "mcpServers": {
    "noaa-climate-mcp-server": {
      "type": "stdio",
      "command": "bunx",
      "args": ["@cyanheads/noaa-climate-mcp-server@latest"],
      "env": {
        "MCP_TRANSPORT_TYPE": "stdio",
        "MCP_LOG_LEVEL": "info",
        "NOAA_CDO_TOKEN": "your-token-here"
      }
    }
  }
}

Or with npx (no Bun required):

{
  "mcpServers": {
    "noaa-climate-mcp-server": {
      "type": "stdio",
      "command": "npx",
      "args": ["-y", "@cyanheads/noaa-climate-mcp-server@latest"],
      "env": {
        "MCP_TRANSPORT_TYPE": "stdio",
        "MCP_LOG_LEVEL": "info",
        "NOAA_CDO_TOKEN": "your-token-here"
      }
    }
  }
}

Or with Docker:

{
  "mcpServers": {
    "noaa-climate-mcp-server": {
      "type": "stdio",
      "command": "docker",
      "args": ["run", "-i", "--rm", "-e", "MCP_TRANSPORT_TYPE=stdio", "-e", "NOAA_CDO_TOKEN=your-token-here", "ghcr.io/cyanheads/noaa-climate-mcp-server:latest"]
    }
  }
}

For Streamable HTTP, set the transport and start the server:

MCP_TRANSPORT_TYPE=http MCP_HTTP_PORT=3010 NOAA_CDO_TOKEN=your-token-here bun run start:http
# Server listens at http://localhost:3010/mcp

Prerequisites

• Bun v1.4.0 or higher (or Node.js ≥24.0.0).
• A free NOAA CDO API token — required for all requests.

Installation

1. Clone the repository:

git clone https://github.com/cyanheads/noaa-climate-mcp-server.git

2. Navigate into the directory:

cd noaa-climate-mcp-server

3. Install dependencies:

bun install

4. Configure environment:

cp .env.example .env
# edit .env and set required vars

Configuration

All configuration is validated at startup via Zod schemas in src/config/server-config.ts. Key environment variables:

Variable	Description	Default
NOAA_CDO_TOKEN	Required. NOAA CDO API token — obtain free at ncdc.noaa.gov/cdo-web/token	—
MCP_TRANSPORT_TYPE	Transport: stdio or http	stdio
MCP_HTTP_PORT	HTTP server port	3010
MCP_HTTP_ENDPOINT_PATH	HTTP endpoint path where the MCP server is mounted	/mcp
MCP_SESSION_MODE	HTTP session posture: stateful, stateless, or auto. Ships as stateless — no tool asks the caller for input mid-handler	stateless
MCP_PUBLIC_URL	Public origin override for TLS-terminating reverse-proxy deployments	none
MCP_AUTH_MODE	Authentication: none, jwt, or oauth	none
MCP_LOG_LEVEL	Log level (debug, info, warning, error, etc.)	info
MCP_GC_PRESSURE_INTERVAL_MS	Opt-in Bun-only forced-GC pressure loop (ms). Try 60000 if heap growth is observed under sustained HTTP load.	0 (disabled)
STORAGE_PROVIDER_TYPE	Storage backend: in-memory, filesystem, supabase, cloudflare-kv/r2/d1	in-memory
OTEL_ENABLED	Enable OpenTelemetry	false

See .env.example for the full list of optional overrides.

Running the server

Local development

• Build and run the production version:

  # One-time build
  bun run rebuild
  
  # Run the built server
  bun run start:http
  # or
  bun run start:stdio
  

• Run checks and tests:

  bun run devcheck  # Lints, formats, type-checks, and more
  bun run test      # Runs the test suite
  bun run test:live # Opt-in: resolves every documented example identifier against the live CDO API
  

Docker

docker build -t noaa-climate-mcp-server .
docker run --rm -e NOAA_CDO_TOKEN=your-token-here -p 3010:3010 noaa-climate-mcp-server

The Dockerfile defaults to HTTP transport, stateless session mode, and logs to /var/log/noaa-climate-mcp-server. OpenTelemetry peer dependencies are installed by default — build with --build-arg OTEL_ENABLED=false to omit them.

Project structure

Directory	Purpose
src/mcp-server/tools	Tool definitions (*.tool.ts). Ten tools across datasets, locations, stations, observations, storm events, and disaster costs.
src/mcp-server/resources	Resource definitions. Datasets catalog and station metadata resources.
src/services/cdo	CDO HTTP client with retry, backoff, camelCase→lowercase parameter translation, and recovery of CDO's own rejection message.
src/services/csv	Incremental RFC 4180 CSV reader shared by the two NCEI bulk-CSV corpora.
src/services/storm-events	NCEI Storm Events bulk-CSV client — filename discovery, streamed decompression, damage parsing.
src/services/billion-dollar-disasters	NCEI Billion-Dollar Disasters client — declared-unit resolution and conversion to whole US dollars.
src/config	Server-specific environment variable parsing and validation with Zod.
tests/	Unit and integration tests, mirroring the src/ structure.

Development guide

See CLAUDE.md for development guidelines and architectural rules. The short version:

• Handlers throw, framework catches — no try/catch in tool logic
• Use ctx.log for logging, ctx.state for storage
• Register new tools and resources in the createApp() arrays
• Wrap external API calls as validate raw → normalize to domain types → return the output schema; never fabricate missing fields

Contributing

Issues are welcome. Run checks and tests before submitting:

bun run devcheck
bun run test

License

This project is licensed under the Apache 2.0 License. See the LICENSE file for details.