If you use the ATC in FSX, you probably noticed when you are in the vicinity of an airport (a certain size), an option on the ATIS.

This is a 'Google automated Translation' of

ATIS (Automatic Terminal Information Service) is a message voice provided by the weather service from the airport. This loops over a predefined frequency.
To view it, (taking as an example a plane parked at Sydney International Airport), open the ATC [ ù ].
Choose  Set on Sydney ATIS 126,250 

A green band containing the message will scroll indefinitely at the top of the screen. 
Tutorial FSX-ATIS

For my example, the message received is as follows :

Information Sydney Airport Golf, 0153 zulu. Wind: calm. Visibility: greater than 20 nautical miles. Sky conditions: partly cloudy to 5700. Temperature: 15. Dew Point: 5.QNH 1013. ILS runway 34L and 34R ILS runway in use. Landing and departing Runway 34L and 34R runway. VFR aircraft should indicate their direction of flight. All devices must collate shutdown instructions. Inform your control at first contact you have received the information Mike.

That contains this message:
- Weather information
- Atmospheric pressure (QNH)
- The runways
- Information on the current procedures

From this information, you can make your first adjustment on the plane (if you have not taken off yet ...), the calibration of the altimeter. To calibrate the altimeter, you will find in the majority of cases knob in a corner of the dial corresponding to the altimeter. Use this button to adjust the air pressure provided by the ATIS, or simply press [ b ].

Tutorial FSX-ATIS

Tutorial Flight Simulator X - ATIS - FSX