TFR information is provided to us every 15 minutes by the FAA and the National Flight Data Center. Generally, on our website, TFRs are updated every 6 minutes. ForeFlight Mobile can take longer to update TFRs depending on the timing between rounds of updates from the source to the server and from the server to the app. Generally, TFRs in the app update every 12 minutes. If your device is connected to the internet, the current TFR information provided to us will be displayed within ForeFlight.
Limitations to consider are the following:
1: If the FAA publishes a TFR without associated graphical shape information it may not be possible for ForeFlight Mobile to show the graphical TFR on the Maps page.
2: TFRs are not always graphically depicted, you should always check the Airports page, under NOTAMs > TFRs for airports along your route, brief your flight, and contact FSS or ATC to confirm that your route does not cross any TFRs.
3: While using an ADS-B receiver, up-to-date graphical TFR information is ONLY displayed if you select the TFR Map layer.
4: TFR data may not be updated or displayed if you are using an ADS-B receiver that does not “replay” data received while the iPad is “asleep” or is not connected. Stratus Replay in the Stratus 2/2S saves 30 minutes of recent TFR data for display when ForeFlight Mobile is reopened. Garmin's GTX-345 does not have a "replay" mode. So it may be best to leave ForeFlight on the entire time you are flying with a particular set-up.
5: TFR data may also not be updated or displayed if the ADS-B receiver is not receiving data from ADS-B towers, or if the ADS-B towers are not broadcasting information about that TFR. Generally speaking, in most parts of the country, you should be able to get adequate coverage if you are 3,000' AGL or higher.
To compensate for the shortcomings of the ADS-B system, we strongly recommend using the Pack feature to capture TFR data prior to departure.
In regard to stadiums, TFRs, FDC 4/3621 is a generic stadium/sporting events TFR. We use a source other than the FAA to identify sporting events that would fall under the restrictions in FDC 4/3621.