NWS weather alerts + forecasts by state/point (api.weather.gov)

Every active National Weather Service alert in the United States as one clean row — event (Tornado Warning, Flood Watch, Heat Advisory, …), severity, urgency, certainty, headline, affected areas and states, onset/expiry, issuing office and the full alert text — filtered by state, severity, urgency, certainty or event name. Or, in forecast mode, the official NWS forecast (7-day half-day periods or hourly) for up to 20 latitude/longitude points. Source: the public api.weather.gov API, no key required.

Data source and status

Publisher	U.S. National Weather Service (NOAA), https://api.weather.gov (documentation)
Alerts	GET /alerts/active?status=actual[&area=…][&severity=…][&urgency=…][&certainty=…][&event=…] — all matching active alerts in one response (the endpoint has no limit parameter; about 300 alerts on a quiet day, far more during severe-weather outbreaks). Test and exercise messages are excluded by status=actual
Forecast	GET /points/{lat},{lon} for the grid, then the grid's forecast (14 half-day periods) or forecastHourly (156 hourly periods)
Refresh cadence	Live on every run. NWS updates the alert feed continuously and forecasts several times a day; each row carries fetched_at, alert rows also the feed's own source_updated time
Terms and licence	NWS data are works of the U.S. Government and not subject to copyright in the U.S. (17 U.S.C. §105). NWS asks API clients to identify themselves (done, see below) and to keep request rates reasonable. This is not a warning service — the Actor does not deliver alerts faster than, or in place of, official channels (NOAA Weather Radio, Wireless Emergency Alerts, weather.gov)
Response guards	The alert/point/period keys measured on 2026-09-04 (id, event, severity, urgency, certainty, headline, areaDesc, geocode.UGC, onset, expires, senderName, description, periods[].temperature, …) must be present; anything else fails the run loudly instead of writing guessed values
Identification	User-Agent: RetrainMap-nws-weather-alerts/0.1 (https://apify.com/retrainmap; <contact>) plus the contact address in the standard From: header

Honesty note: states on an alert row is derived from the alert's UGC zone/county codes (FLZ041 → FL), because the API does not carry a state field; marine zones yield NWS marine area codes (AM, GM, PZ, …). description and instruction are cut at 3,000 characters (flagged by *_truncated); the full text is one click away at nws_url.

Input

Field	Type	Meaning
mode	alerts / forecast	Default alerts
states	array of 2-letter codes	Alerts. Empty (default) = the whole country. Marine area codes accepted
severity	Extreme Severe Moderate Minor Unknown	Optional
urgency	Immediate Expected Future Past Unknown	Optional
certainty	Observed Likely Possible Unlikely Unknown	Optional
events	array of exact NWS event names	Optional, e.g. Tornado Warning
points	array of "lat,lon"	Forecast; up to 20 U.S. points
forecast_type	daily / hourly	Default daily (14 periods per point)
max_records	integer	Default 300
request_interval_ms	integer	Default 500 (floor 250)
contact_email	string	Sent in the User-Agent and From: header

Examples:

{ "mode": "alerts", "states": ["TX", "OK", "KS"], "severity": ["Extreme", "Severe"], "urgency": ["Immediate", "Expected"] }

{ "mode": "forecast", "points": ["40.7128,-74.0060", "34.0522,-118.2437"], "forecast_type": "daily" }

Output (dataset row)

Alerts: id, event, severity, urgency, certainty, status, message_type, category, response, headline, area_desc, states, ugc_zones, same_codes, sent, effective, onset, expires, ends, sender, sender_name, description (≤ 3,000 chars), description_truncated, instruction, instruction_truncated, nws_url, source_updated, fetched_at.

Forecast: point, latitude, longitude, grid_id, grid_x, grid_y, forecast_office, nearest_city, nearest_state, time_zone, forecast_type, period_number, period_name, start_time, end_time, is_daytime, temperature, temperature_unit, temperature_trend, precip_probability_pct, dewpoint_c and relative_humidity_pct (hourly), wind_speed, wind_direction, short_forecast, detailed_forecast, icon, forecast_generated_at, forecast_updated_at, fetched_at.

A run summary (filters, the exact API requests made, counts, the feed's update time) is stored as RUN_SUMMARY in the run's key-value store.

Pricing (pay per event)

Event	Price
run-start — once per run	$0.10
record — per row written	$0.005

The default run (up to 300 alerts) costs at most $1.60; a 7-day forecast for one point (14 rows) $0.17. Rows stop when your run's maximum charge is reached; the run summary says so.

Operator

Steelyard Ventures LLC (RetrainMap) — info@steelyardclinical.com. The Actor writes only to its own dataset and key-value store; it stores no credentials and sends nothing but GET requests.