This quote from the book describes a storm. “A roil of brown loomed over the mountains.” (p.147) Describe the storm. Why is it so dangerous?

The above quote describes the dust storm as it overtakes the valley. The dust suffocates everything it touches, and it also poses physical problems for those exposed to the dust spores that coat and grow in the lungs. Esperanaza's suffers from this illness... Valley Fever.