# NOAA SPC Severe Weather Outlook by Coordinate

> NOAA SPC Severe Weather Outlook by Coordinate is a paid API for AI agents from saylorinnovations.com, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-30).

Returns NOAA Storm Prediction Center severe weather risk categories for days 1–3 and day 1 tornado, damaging wind, and large hail probabilities for a given US lat/lon.

## Facts

- Endpoint: GET https://saylorinnovations.com/api/weather/severe-outlook?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-30
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/noaa-spc-severe-weather-outlook-by-coordinate-e44f8c99
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_QwKXOLP6DUpM9RLig7KI2

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability noaa-spc-severe-weather-outlook-by-coordinate-e44f8c99
```

Example prompt: What's the NOAA SPC severe weather outlook for the next 3 days at latitude 36.15, longitude -95.99? I want to know the risk category each day and whether there's any tornado or large hail probability on day 1.

## When to prefer this

Use this endpoint when you need structured, per-day NOAA SPC severe weather risk categories and day 1 hazard probabilities (tornado, wind, hail) for a specific US coordinate. Prefer this over general weather APIs when the use case specifically requires SPC convective outlook data (TSTM/MRGL/SLGT/ENH/MDT/HIGH classifications) rather than temperature or precipitation forecasts.

## Known failure modes

- Missing or invalid lat/lon query parameters — returns validation error
- Coordinates outside the contiguous United States — may return NONE risk or an error
- NOAA SPC data temporarily unavailable — upstream fetch failure
- Coordinates on the boundary of outlook polygons may produce ambiguous results
- Outlook not yet issued for a future day — may return null for day 2 or day 3 entries

## How this service works

NOAA SPC severe weather outlook at a coordinate - risk category for days 1 to 3 and day 1 tornado, damaging wind and large hail probabilities

## Output

Returns an array of outlook entries for days 1–3, each with the SPC risk name (e.g. SLGT, ENH, MDT, HIGH), category code, validity window, issue time, and forecaster. Also includes a boolean any_severe_risk flag, highest risk in the 3-day window with its day, and day 1 specific probabilities for tornado, damaging wind, and large hail. A note field provides context for interpreting the result and a source field identifies the data origin.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "lat",
      "lon"
     ],
     "properties": {
      "lat": {
       "type": "string",
       "description": "Latitude (United States)"
      },
      "lon": {
       "type": "string",
       "description": "Longitude (United States)"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "json"
    },
    "example": {
     "type": "object",
     "required": [
      "outlook",
      "any_severe_risk"
     ],
     "properties": {
      "lat": {
       "type": "number",
       "description": "Latitude in decimal degrees"
      },
      "lon": {
       "type": "number",
       "description": "Longitude in decimal degrees"
      },
      "note": {
       "type": "string",
       "description": "Caveat or context for reading the result"
      },
      "source": {
       "type": "string",
       "description": "Data source the values come from"
      },
      "outlook": {
       "type": "array",
       "items": {
        "type": "object",
        "properties": {
         "day": {
          "type": [
           "number",
           "null"
          ],
          "description": "Outlook day, 1 to 3"
         },
         "risk": {
          "type": [
           "string",
           "null"
          ],
          "description": "Risk name"
         },
         "valid": {
          "description": "True when the input passed validation"
         },
         "issued": {
          "type": [
           "string",
           "null"
          ],
          "description": "Issued at (UTC)"
         },
         "expires": {
          "type": [
           "string",
           "null"
          ],
          "description": "Valid until (UTC)"
         },
         "category": {
          "description": "Category"
         },
         "forecaster": {
          "type": [
           "string",
           "null"
          ],
          "description": "Forecaster names"
         },
         "description": {
  
… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/noaa-spc-severe-weather-outlook-by-coordinate-e44f8c99/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from saylorinnovations.com](https://www.zero.xyz/host/saylorinnovations.com/llms.txt)