What is likely to occur at an airport near sea level with an external temperature of 0°C?

At an airport near sea level with an external temperature of 0°C, the likelihood of ice formation on runways is significant. At this temperature, any moisture on the runway can freeze, leading to hazardous conditions for aircraft operations. Ice can create a slick surface, increasing the risk of skidding during takeoff and landing, which poses severe safety concerns.

In contrast, while strong thermal updrafts typically occur on hot days due to rising warm air, low humidity levels can be variable and do not necessarily correlate directly with 0°C at sea level. Increased visibility is not a guaranteed outcome under these conditions either, as ice formation often occurs in conditions with moisture, which can lead to reduced visibility due to fog or other weather phenomena. Therefore, the primary concern in this scenario is the risk of ice formation on runways.