Final answer:
The location of the Imperial Valley, east of the Laguna Mountains, affects humidity in San Diego and the Imperial Valley.
Step-by-step explanation:
The location of the Imperial Valley, east of the Laguna Mountains, significantly influences the general trends in humidity in San Diego and the Imperial Valley. As air is forced to rise when it encounters the mountains, it cools and condenses, causing precipitation to occur on the windward side (west) of the mountains. This results in higher humidity levels in San Diego, located west of the Laguna Mountains, compared to the Imperial Valley, which is situated east of the mountains and therefore does not receive as much moisture.
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