nws-weather-mcp-server

Nws Get Observations

nws_get_observations

Read-only

Get current weather observations (actual measured conditions). Accepts coordinates (resolves nearest station automatically) or a station ID directly (e.g., "KSEA").

Input Schema

TableJSON Schema

Name	Required	Description
`latitude`	No	Latitude for automatic station resolution. Use with longitude. Ignored if station_id is provided.
`longitude`	No	Longitude for automatic station resolution. Use with latitude. Ignored if station_id is provided.
`station_id`	No	Station identifier directly (e.g., "KSEA", "KORD"). Use nws_find_stations to discover station IDs.

Output Schema

TableJSON Schema

Name	Required	Description
`error`	No	Present when the call failed. Absent on success.
`notice`	No	Guidance when the latest observation is more than 2 hours old — data may not reflect current conditions.
`station`	No	Station ID that served the observation (e.g., "KSEA")
`timeZone`	No	Station time zone when known
`dewpointC`	No	Dewpoint in Celsius
`stationId`	No	Observation station ID
`timestamp`	No	Observation time (ISO 8601)
`heatIndexC`	No	Heat index in Celsius
`observedAt`	No	Observation timestamp (ISO 8601)
`windChillC`	No	Wind chill in Celsius
`cloudLayers`	No	Cloud layer information
`stationName`	No	Station name
`visibilityM`	No	Visibility in meters
`windGustKmh`	No	Wind gust in km/h
`temperatureC`	No	Temperature in Celsius
`windSpeedKmh`	No	Wind speed in km/h
`textDescription`	No	Conditions summary (e.g., "Mostly Cloudy")
`windDirectionDeg`	No	Wind direction in degrees (0-360)
`relativeHumidityPct`	No	Relative humidity in percent (0-100)
`barometricPressurePa`	No	Barometric pressure in Pascals

Schema Changelog

Changes observed during successful MCP inspections.

Changed1 schema field changedSep 19, 2026

changedOutput schema / properties / error / properties / data / properties / reason / description

Previous value: -"Machine-readable failure mode. Declared by this tool: `missing_input`: Neither station_id nor a (latitude, longitude) pair was provided `blank_station_id`: station_id was provided with a blank value `station_not_found`: Station ID does not exist in the NWS network `no_observations`: Station has no recent observations available `no_stations_nearby`: No observation stations exist near the requested coordinates `out_of_scope`: Coordinates fall outside US National Weather Service coverage Other values are possible when a failure originates below the handler."New value: +"Machine-readable failure mode. Declared by this tool: `missing_input`: Neither station_id nor a (latitude, longitude) pair was provided. `blank_station_id`: station_id was provided with a blank value. `station_not_found`: Station ID does not exist in the NWS network. `no_observations`: Station has no recent observations available. `no_stations_nearby`: No observation stations exist near the requested coordinates. `out_of_scope`: Coordinates fall outside US National Weather Service coverage. Other values are possible when a failure originates below the handler."

Changed24 schema fields changedSep 4, 2026

removedOutput schema / properties / barometricPressurePa / anyOf

Removed value: -[
-  {
-    "type": "number"
-  },
-  {
-    "type": "null"
-  }
-]

addedOutput schema / properties / barometricPressurePa / type
```
Added value: +[
+  "number",
+  "null"
+]
```

removedOutput schema / properties / cloudLayers / items / properties / baseM / anyOf

Removed value: -[
-  {
-    "type": "number"
-  },
-  {
-    "type": "null"
-  }
-]

addedOutput schema / properties / cloudLayers / items / properties / baseM / type
```
Added value: +[
+  "number",
+  "null"
+]
```

removedOutput schema / properties / dewpointC / anyOf

Removed value: -[
-  {
-    "type": "number"
-  },
-  {
-    "type": "null"
-  }
-]

addedOutput schema / properties / dewpointC / type
```
Added value: +[
+  "number",
+  "null"
+]
```

removedOutput schema / properties / heatIndexC / anyOf

Removed value: -[
-  {
-    "type": "number"
-  },
-  {
-    "type": "null"
-  }
-]

addedOutput schema / properties / heatIndexC / type
```
Added value: +[
+  "number",
+  "null"
+]
```

removedOutput schema / properties / relativeHumidityPct / anyOf

Removed value: -[
-  {
-    "type": "number"
-  },
-  {
-    "type": "null"
-  }
-]

addedOutput schema / properties / relativeHumidityPct / type
```
Added value: +[
+  "number",
+  "null"
+]
```

removedOutput schema / properties / temperatureC / anyOf

Removed value: -[
-  {
-    "type": "number"
-  },
-  {
-    "type": "null"
-  }
-]

addedOutput schema / properties / temperatureC / type
```
Added value: +[
+  "number",
+  "null"
+]
```

removedOutput schema / properties / timeZone / anyOf

Removed value: -[
-  {
-    "type": "string"
-  },
-  {
-    "type": "null"
-  }
-]

addedOutput schema / properties / timeZone / type
```
Added value: +[
+  "string",
+  "null"
+]
```

removedOutput schema / properties / visibilityM / anyOf

Removed value: -[
-  {
-    "type": "number"
-  },
-  {
-    "type": "null"
-  }
-]

addedOutput schema / properties / visibilityM / type
```
Added value: +[
+  "number",
+  "null"
+]
```

removedOutput schema / properties / windChillC / anyOf

Removed value: -[
-  {
-    "type": "number"
-  },
-  {
-    "type": "null"
-  }
-]

addedOutput schema / properties / windChillC / type
```
Added value: +[
+  "number",
+  "null"
+]
```

removedOutput schema / properties / windDirectionDeg / anyOf

Removed value: -[
-  {
-    "type": "number"
-  },
-  {
-    "type": "null"
-  }
-]

addedOutput schema / properties / windDirectionDeg / type
```
Added value: +[
+  "number",
+  "null"
+]
```

removedOutput schema / properties / windGustKmh / anyOf

Removed value: -[
-  {
-    "type": "number"
-  },
-  {
-    "type": "null"
-  }
-]

addedOutput schema / properties / windGustKmh / type
```
Added value: +[
+  "number",
+  "null"
+]
```

removedOutput schema / properties / windSpeedKmh / anyOf

Removed value: -[
-  {
-    "type": "number"
-  },
-  {
-    "type": "null"
-  }
-]

addedOutput schema / properties / windSpeedKmh / type
```
Added value: +[
+  "number",
+  "null"
+]
```

Changed6 schema fields changedAug 25, 2026

changedInput schema / $schema

Previous value: -"http://json-schema.org/draft-07/schema#"New value: +"https://json-schema.org/draft/2020-12/schema"

addedInput schema / additionalProperties
```
Added value: +false
```

changedOutput schema / $schema

Previous value: -"http://json-schema.org/draft-07/schema#"New value: +"https://json-schema.org/draft/2020-12/schema"

addedOutput schema / anyOf

Added value: +[
+  {
+    "not": {
+      "required": [
+        "error"
+      ]
+    },
+    "required": [
+      "stationId",
+      "stationName",
+      "timestamp",
+      "timeZone",
+      "textDescription",
+      "temperatureC",
+      "dewpointC",
+      "windSpeedKmh",
+      "windDirectionDeg",
+      "windGustKmh",
+      "barometricPressurePa",
+      "visibilityM",
+      "relativeHumidityPct",
+      "heatIndexC",
+      "windChillC",
+      "cloudLayers",
+      "station",
+      "observedAt"
+    ]
+  },
+  {
+    "required": [
+      "error"
+    ]
+  }
+]

addedOutput schema / properties / error

Added value: +{
+  "additionalProperties": {},
+  "description": "Present when the call failed. Absent on success.",
+  "properties": {
+    "code": {
+      "description": "JSON-RPC error code for this failure.",
+      "maximum": 9007199254740991,
+      "minimum": -9007199254740991,
+      "type": "integer"
+    },
+    "data": {
+      "additionalProperties": {},
+      "properties": {
+        "reason": {
+          "description": "Machine-readable failure mode. Declared by this tool: `missing_input`: Neither station_id nor a (latitude, longitude) pair was provided `blank_station_id`: station_id was provided with a blank value `station_not_found`: Station ID does not exist in the NWS network `no_observations`: Station has no recent observations available `no_stations_nearby`: No observation stations exist near the requested coordinates `out_of_scope`: Coordinates fall outside US National Weather Service coverage Other values are possible when a failure originates below the handler.",
+          "examples": [
+            "missing_input",
+            "blank_station_id",
+            "station_not_found",
+            "no_observations",
+            "no_stations_nearby",
+            "out_of_scope"
+          ],
+          "type": "string"
+        },
+        "recovery": {
+          "additionalProperties": {},
+          "description": "Actionable next step for the caller.",
+          "properties": {
+            "hint": {
+              "type": "string"
+            }
+          },
+          "required": [
+            "hint"
+          ],
+          "type": "object"
+        },
+        "retryable": {
+          "description": "Whether retrying may succeed.",
+          "type": "boolean"
+        }
+      },
+      "type": "object"
+    },
+    "message": {
+      "description": "Human-readable description of what went wrong.",
+      "type": "string"
+    }
+  },
+  "required": [
+    "code",
+    "message"
+  ],
+  "type": "object"
+}

removedOutput schema / required

Removed value: -[
-  "stationId",
-  "stationName",
-  "timestamp",
-  "timeZone",
-  "textDescription",
-  "temperatureC",
-  "dewpointC",
-  "windSpeedKmh",
-  "windDirectionDeg",
-  "windGustKmh",
-  "barometricPressurePa",
-  "visibilityM",
-  "relativeHumidityPct",
-  "heatIndexC",
-  "windChillC",
-  "cloudLayers",
-  "station",
-  "observedAt"
-]

Changed4 schema fields changedMay 30, 2026

addedOutput schema / properties / notice

Added value: +{
+  "description": "Guidance when the latest observation is more than 2 hours old — data may not reflect current conditions.",
+  "type": "string"
+}

addedOutput schema / properties / observedAt

Added value: +{
+  "description": "Observation timestamp (ISO 8601)",
+  "type": "string"
+}

addedOutput schema / properties / station

Added value: +{
+  "description": "Station ID that served the observation (e.g., \"KSEA\")",
+  "type": "string"
+}

changedOutput schema / required

Previous value: -[
-  "stationId",
-  "stationName",
-  "timestamp",
-  "timeZone",
-  "textDescription",
-  "temperatureC",
-  "dewpointC",
-  "windSpeedKmh",
-  "windDirectionDeg",
-  "windGustKmh",
-  "barometricPressurePa",
-  "visibilityM",
-  "relativeHumidityPct",
-  "heatIndexC",
-  "windChillC",
-  "cloudLayers"
-]New value: +[
+  "stationId",
+  "stationName",
+  "timestamp",
+  "timeZone",
+  "textDescription",
+  "temperatureC",
+  "dewpointC",
+  "windSpeedKmh",
+  "windDirectionDeg",
+  "windGustKmh",
+  "barometricPressurePa",
+  "visibilityM",
+  "relativeHumidityPct",
+  "heatIndexC",
+  "windChillC",
+  "cloudLayers",
+  "station",
+  "observedAt"
+]

Changed24 schema fields changedMay 16, 2026

removedOutput schema / properties / barometricPressure

Removed value: -{
-  "anyOf": [
-    {
-      "type": "number"
-    },
-    {
-      "type": "null"
-    }
-  ],
-  "description": "Barometric pressure in Pascals"
-}

addedOutput schema / properties / barometricPressurePa

Added value: +{
+  "anyOf": [
+    {
+      "type": "number"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "description": "Barometric pressure in Pascals"
+}

removedOutput schema / properties / cloudLayers / items / properties / base

Removed value: -{
-  "anyOf": [
-    {
-      "type": "number"
-    },
-    {
-      "type": "null"
-    }
-  ],
-  "description": "Cloud base height in meters"
-}

addedOutput schema / properties / cloudLayers / items / properties / baseM

Added value: +{
+  "anyOf": [
+    {
+      "type": "number"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "description": "Cloud base height in meters"
+}

changedOutput schema / properties / cloudLayers / items / required

Previous value: -[
-  "amount",
-  "base"
-]New value: +[
+  "amount",
+  "baseM"
+]

removedOutput schema / properties / dewpoint

Removed value: -{
-  "anyOf": [
-    {
-      "type": "number"
-    },
-    {
-      "type": "null"
-    }
-  ],
-  "description": "Dewpoint in Celsius"
-}

addedOutput schema / properties / dewpointC

Added value: +{
+  "anyOf": [
+    {
+      "type": "number"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "description": "Dewpoint in Celsius"
+}

removedOutput schema / properties / heatIndex

Removed value: -{
-  "anyOf": [
-    {
-      "type": "number"
-    },
-    {
-      "type": "null"
-    }
-  ],
-  "description": "Heat index in Celsius"
-}

addedOutput schema / properties / heatIndexC

Added value: +{
+  "anyOf": [
+    {
+      "type": "number"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "description": "Heat index in Celsius"
+}

removedOutput schema / properties / relativeHumidity

Removed value: -{
-  "anyOf": [
-    {
-      "type": "number"
-    },
-    {
-      "type": "null"
-    }
-  ],
-  "description": "Relative humidity (%)"
-}

addedOutput schema / properties / relativeHumidityPct

Added value: +{
+  "anyOf": [
+    {
+      "type": "number"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "description": "Relative humidity in percent (0-100)"
+}

removedOutput schema / properties / temperature

Removed value: -{
-  "anyOf": [
-    {
-      "type": "number"
-    },
-    {
-      "type": "null"
-    }
-  ],
-  "description": "Temperature in Celsius"
-}

addedOutput schema / properties / temperatureC

Added value: +{
+  "anyOf": [
+    {
+      "type": "number"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "description": "Temperature in Celsius"
+}

removedOutput schema / properties / visibility

Removed value: -{
-  "anyOf": [
-    {
-      "type": "number"
-    },
-    {
-      "type": "null"
-    }
-  ],
-  "description": "Visibility in meters"
-}

addedOutput schema / properties / visibilityM

Added value: +{
+  "anyOf": [
+    {
+      "type": "number"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "description": "Visibility in meters"
+}

removedOutput schema / properties / windChill

Removed value: -{
-  "anyOf": [
-    {
-      "type": "number"
-    },
-    {
-      "type": "null"
-    }
-  ],
-  "description": "Wind chill in Celsius"
-}

addedOutput schema / properties / windChillC

Added value: +{
+  "anyOf": [
+    {
+      "type": "number"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "description": "Wind chill in Celsius"
+}

removedOutput schema / properties / windDirection

Removed value: -{
-  "anyOf": [
-    {
-      "type": "number"
-    },
-    {
-      "type": "null"
-    }
-  ],
-  "description": "Wind direction in degrees"
-}

addedOutput schema / properties / windDirectionDeg

Added value: +{
+  "anyOf": [
+    {
+      "type": "number"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "description": "Wind direction in degrees (0-360)"
+}

removedOutput schema / properties / windGust

Removed value: -{
-  "anyOf": [
-    {
-      "type": "number"
-    },
-    {
-      "type": "null"
-    }
-  ],
-  "description": "Wind gust in km/h"
-}

addedOutput schema / properties / windGustKmh

Added value: +{
+  "anyOf": [
+    {
+      "type": "number"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "description": "Wind gust in km/h"
+}

removedOutput schema / properties / windSpeed

Removed value: -{
-  "anyOf": [
-    {
-      "type": "number"
-    },
-    {
-      "type": "null"
-    }
-  ],
-  "description": "Wind speed in km/h"
-}

addedOutput schema / properties / windSpeedKmh

Added value: +{
+  "anyOf": [
+    {
+      "type": "number"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "description": "Wind speed in km/h"
+}

changedOutput schema / required

Previous value: -[
-  "stationId",
-  "stationName",
-  "timestamp",
-  "timeZone",
-  "textDescription",
-  "temperature",
-  "dewpoint",
-  "windSpeed",
-  "windDirection",
-  "windGust",
-  "barometricPressure",
-  "visibility",
-  "relativeHumidity",
-  "heatIndex",
-  "windChill",
-  "cloudLayers"
-]New value: +[
+  "stationId",
+  "stationName",
+  "timestamp",
+  "timeZone",
+  "textDescription",
+  "temperatureC",
+  "dewpointC",
+  "windSpeedKmh",
+  "windDirectionDeg",
+  "windGustKmh",
+  "barometricPressurePa",
+  "visibilityM",
+  "relativeHumidityPct",
+  "heatIndexC",
+  "windChillC",
+  "cloudLayers"
+]

Changed1 schema field changedApr 24, 2026
- addedOutput schema / properties / cloudLayers / items / description
```
Added value: +"Single cloud layer with cover amount and base height"
```

Changed2 schema fields changedApr 14, 2026

addedOutput schema / properties / timeZone

Added value: +{
+  "anyOf": [
+    {
+      "type": "string"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "description": "Station time zone when known"
+}

changedOutput schema / required

Previous value: -[
-  "stationId",
-  "stationName",
-  "timestamp",
-  "textDescription",
-  "temperature",
-  "dewpoint",
-  "windSpeed",
-  "windDirection",
-  "windGust",
-  "barometricPressure",
-  "visibility",
-  "relativeHumidity",
-  "heatIndex",
-  "windChill",
-  "cloudLayers"
-]New value: +[
+  "stationId",
+  "stationName",
+  "timestamp",
+  "timeZone",
+  "textDescription",
+  "temperature",
+  "dewpoint",
+  "windSpeed",
+  "windDirection",
+  "windGust",
+  "barometricPressure",
+  "visibility",
+  "relativeHumidity",
+  "heatIndex",
+  "windChill",
+  "cloudLayers"
+]

First observedApr 13, 2026

TDQS

A4.3/5.0

Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations only flag readOnlyHint. The description adds meaningful behavior: coordinate resolution automatically picks the nearest station, and station_id bypasses that. It doesn't hide side effects, which are minimal for a read operation, and it does not contradict annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Two sentences, front-loads the core purpose and includes the necessary invocation options plus an example. No filler or redundancy.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

This is a simple optional-parameter read tool; the description explains both valid input modes and the automatic station-resolution behavior. The output schema and readOnlyHint cover return values and safety, so nothing essential is missing for correct invocation.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The input schema already has 100% coverage, including 'automatic station resolution', 'Ignored if station_id is provided', and examples. The description adds no parameter meaning beyond what the schema provides, so baseline 3 is appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description uses a specific verb ('Get'), states the resource ('current weather observations'), and clarifies 'actual measured conditions' to distinguish from forecasts. It also enumerates accepted input forms (coordinates or station ID), making the tool's purpose unmistakable even among siblings like nws_get_forecast.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description gives clear context that this is for current observations and explains the two invocation modes, including that coordinates auto-resolve a station. It doesn't spell out exclusions versus forecast-related siblings, but the phrase 'actual measured conditions' implicitly routes the agent to observations rather than forecasts.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

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Nws Get Observations

Input Schema

Output Schema

Schema Changelog

TDQS

Glama MCP Gateway

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