In narrative description a place or character drives the story, it sets the mood. Sight, sound, taste, smell, and feel the surroundings or conflict with another character. Crisp air is an example to set the mood for a reader. The reader is shown by surroundings, and with characters in descriptive action. Narrative moves the story forward. The flow of the following paragraph increases drama and the reader will want to know what happens next. The progression of events or what comes next with description engage the reader.
Slightly to his right, just below the mountain top a gigantic shimmering red flat cloud was forming. Throughout the cloud there were small bright white flashes, and then they stopped. Now taking shape from the cloud, a red glowing disk had appeared on the mountain side.
The next paragraph is how he reacts to the red glowing disk. Narrative can be used to help develop a character and settings. What you clearly define in your experience, is the reaction you want your reader to be involved in.
Use narrative instead when characters are having too much dialogue with their personal thoughts.
Sound, Smell, Feel: Cold air was bringing the heavy mold smell of old growth forest into the van, Nancy shivered. Near the road a loud low to chilling high pitched scream pierced the air lingering. It turned to rolling shrill screams; and ended with deep coughing, it was a mountain lion. That gave Nancy another reason to shiver, she immediately closed her window.
Taste: “Coffee yes that sounds good,” Knoton said, standing in the office door. He breathed in, the air distinctly smelled of coffee. He raised his coffee cup.
Conflict: They had walked to where Nar sat. He thought he had been talking too quietly for Nar to hear him but he was wrong.
Nar gave them a cool gaze and smiled. “We are at the pick-up site.”
Nar watched the loading crew walk silently back across the war room and the entry doors slid solidly shut behind them.