Workload; Confusion; Human-Machine Interface
Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural FAR
Equipment / Tooling; Human Factors
The TAF for ZZZ is NOT done by the NWS but contracted to [a company] to issue an Enhanced Weather Information System (EWINS) TAF. This shows up in our [dispatch computer] and is emailed to a conference where I can find it. The TAF does not automatically go into our airline planning tools or the flight crew packet but must be copied and pasted into our weather system in order to be easily seen by the dispatcher and for the crew to have it.An old EWINS TAF from 3 days earlier was still in the system and I failed to notice the date was incorrect. After the flight was airborne to ZZZ I noticed that an amended TAF had popped into my [dispatch computer]. I then went to compare the new TAF to the one in the system and then noticed the date was wrong on the one which I used to dispatch the flight. I also checked the flight paperwork packet that the crew used and it contained the TAF from 3 days earlier.FAR 121.601(b) before beginning a flight; the aircraft dispatcher shall provide the pilot in command with all available weather reports and forecasts of weather phenomena that may affect the safety of flight.I failed to provide the crew with the current EWINS TAF for ZZZ before departure.I sent the flight crew the current ZZZ TAF via ACARs and they acknowledged receiving it.We should have an automated system to have EWINS TAFs entered into our primary dispatch tools. TAFs should be deleted from our primary system when they are no longer valid. I would have noticed if there was no TAF in the system.I have added a [dispatch] Pop Up Alert to check that a valid TAF is in the system for ZZZ as a double check.
Dispatcher reported dispatching a flight with an old Terminal Area Forecast (TAF) that was still in the system from days earlier and not noticing it was out of date until an amended TAF popped up; with the aircraft already in flight.