What combination leads to a Red flag Warning?

A Red Flag Warning is issued when specific combinations of weather conditions enhance the potential for wildfires to ignite and spread quickly. The correct answer emphasizes the significance of both high fire danger indicators—such as fuel dryness and temperature—and critical weather patterns, including wind speed and moisture levels in the air.

When conditions are classified as having high fire danger, it typically means that vegetation is extremely dry and susceptible to ignition. Coupled with critical weather patterns, such as strong winds or low humidity, these factors can lead to rapid fire growth and increased potential for large-scale wildfires. This warning serves to alert fire management personnel and the public to the heightened risk, allowing for preparation and preventive measures to be implemented.

The other combinations presented do not meet the specific criteria that define a Red Flag Warning. For example, while extreme heat and dry vegetation can contribute to fire danger, they are not sufficient alone without considering weather patterns. Similarly, low humidity and wind patterns are crucial, but alone do not encapsulate the full danger of high fire risk along with other influencing factors. Heavy rainfall and moisture content, on the other hand, typically reduce fire risk, making this combination counterproductive to the conditions that warrant a Red Flag Warning.