As the Perseverance Rover approaches Mars, NASA mysteriously remove the countdown clock to the landing. Fear not, the countdown clocks on this site are still working: Perseverance Rover. Note that after the landing, the page will reflect the current mission time and other data made available.
I have been informed that weather data will be made available from NASA via their servers in the same way that I fetch the weather data from the InSight lander, but the data portal will take a few weeks to setup. Since weather data from InSight is becoming sparse and next to useless (it has now reached the end of its original mission and is beginning an extension), it will be a relief to have more data available.
Perseverance has an equivalent weather monitoring suite to InSight, but also includes humidity data, a first on Mars.