TFR (Temporary Flight Restriction) monitoring for events tells you when the FAA has put a no-fly zone over — or near — your venue. TFRs aren't routine. When the President arrives at a city, when a wildfire is being actively fought from the air, when a major sporting event has stadium-overflight restrictions filed, the FAA publishes a TFR. SignalGuard checks the active TFR list every scan and tells you when any of those footprints overlap your event.
What this signal monitors
The TFR signal reports every active FAA Temporary Flight Restriction whose polygon footprint or centroid falls within a configurable radius (default 80 km) of the venue. Each TFR includes its NOTAM key, title, LEGAL classification (SECURITY, VIP, HAZARDS, AIRSHOW, SPORTING, SPACE, DISASTER/RELIEF, EMERGENCY), the polygon centroid, the nearest vertex distance to the venue, and the last-modified timestamp.
Data sources
SignalGuard's faaTfrClient.js queries the FAA's GeoServer WFS endpoint at tfr.faa.gov/geoserver/TFR/ows requesting the TFR:V_TFR_LOC layer in GeoJSON. Free, no API key, returns every active TFR nationwide (typically 50–100 at any given moment). The client tests "near venue" two ways: centroid distance and nearest-polygon-vertex distance. The nearest-vertex check catches large TFRs (wildfire perimeters, presidential movement TFRs spanning multiple counties) whose centroid is far away but whose actual footprint clips into the event zone. The FAA also publishes TFRs textually through the FAA NOTAM search; the WFS feed is the same dataset in machine-readable form.
How SignalGuard scores severity
LEGAL classification drives severity. SECURITY, VIP, PRESIDENT, and EMERGENCY TFRs within 25 km of the venue escalate to high; further than 25 km is medium. HAZARDS, DISASTER, and RELIEF TFRs follow the same distance-tiered rule (a wildfire-fighting TFR 30 km away is still operationally relevant). AIRSHOW and SPACE TFRs are medium. SPORTING TFRs are low unless your event is the sporting event in question. Anything else inside 10 km is medium; further is low. The overall level is the max across all matched TFRs. Distance is taken as the lesser of centroid distance and nearest-vertex distance — for large irregular TFRs the vertex distance is the operationally honest number.
Use cases for event security
- Hold doors when this signal is HIGH because a Presidential movement TFR is live within 25 km. A SECURITY-type TFR within the inner ring during your event window means Secret Service movement is happening and the local airspace is heavily scrutinized. Cross-coordinate with the venue's law enforcement liaison; expect motorcade-related road closures (see traffic monitoring).
- Wildfire airspace deconfliction. A HAZARDS TFR within 50 km of the venue means firefighting aircraft are actively working — any media or commercial drone operation near your event needs to be re-coordinated with the IC running the fire. This is a contract and liability question, not just an operational one.
- Airshow conflict detection. An AIRSHOW TFR a city away from your event still affects your local airspace — formation flights and demonstration teams routinely transit at low altitude between airshow sites and base airports. Expect helicopter and small fixed-wing density on the airspace card.
Pairs well with
- Airspace monitoring — the live aircraft inside the restricted footprint.
- FAA NOTAM monitoring — the broader airspace notice context including drone and parachute activity.
- Traffic monitoring — VIP TFRs almost always come with ground-route closures.
Premium upgrade path
The FAA WFS feed is authoritative for US TFRs. For international airspace restrictions (Notices to Airmen issued by ICAO members), BYOK Lufthansa Systems NOTAM API, SkyVector's commercial feed, or Foreflight Enterprise on the Integrations page. For predictive airspace planning (TFRs that are commonly filed before they're published), ATCEUC's restricted-area datasets and Eurocontrol's NM API supplement the FAA-only path. See the SignalGuard docs hub.
Frequently asked questions
What's the difference between TFRs and NOTAMs for event security? Every TFR is a NOTAM, but most NOTAMs are not TFRs. TFRs specifically establish restricted airspace; NOTAMs cover any airspace condition — runway closures, NAVAID outages, drone operations, parachute jumps, and TFRs themselves. SignalGuard has a dedicated NOTAM signal for the broader category.
Does SignalGuard alert me to TFRs filed for my event? Yes — if you file a TFR for your own event (common for major festivals and sporting events), it appears in the signal alongside any other active TFRs.
How often does the TFR list update? The FAA publishes TFRs as they're issued; SignalGuard caches the list for 5 minutes per venue. Rescans pull a fresh list.
Are TFRs only a US concept?
The term "TFR" is FAA-specific. Other ICAO members publish equivalent airspace restrictions as NOTAMs or as country-specific designations. SignalGuard supports international airspace restrictions via BYOK providers on /integrations.
Can I export TFR data to my COP/CAD system? Yes — Enterprise plans include TFR data in the standard API export. See pricing.
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