NOTAMs are Notices to Airmen provided by the Federal Aviation Administration. They are warnings of hazards aircraft may encounter en route to a destination. Hazards could include but are not limited to:
Flights by important people like heads of state
Inoperable lights on tall obstructions
Inoperable navigational aids
Military exercises with airspace restrictions
You can get current NOTAMS for McKinney National Airport on the FAA website. The FAA Identifier for McKinney National Airport is KTKI.