During what conditions should caution be exercised regarding extreme weather limits for the CRJ 900?

Caution should be exercised during heavy snow and ice, strong thunderstorms, and high winds when operating the CRJ 900 because these extreme weather conditions can significantly impact the aircraft's performance and safety.

In heavy snow and ice conditions, there is a risk of reduced visibility and degraded runway conditions, which can affect takeoff and landing performance. Ice accumulation on the wings and control surfaces can impact the aircraft's lift and handling characteristics, leading to potentially hazardous situations.

Strong thunderstorms present challenges, including severe turbulence, lightning, and wind shear, which can affect the aircraft's stability and control. These conditions can also result in microbursts, which pose a significant threat during takeoff and landing phases.

High winds, especially crosswinds or gusty conditions, can make maintaining control of the aircraft difficult during takeoff and landing. Understanding the aircraft's limitations in these scenarios is crucial for ensuring safe operations.

Given that each of these extreme weather elements poses unique risks to the safety and performance of the CRJ 900, it is essential to consider all of them and exercise caution accordingly. This comprehensive awareness is vital for pilots to make informed decisions regarding flight operations in adverse weather.