You are tasked with addressing latency issues in a web application hosted on App Engine, utilizing CloudSQL and Cloud Storage for data storage. Despite a traffic spike subsiding, users continue to encounter prolonged latency. Upon investigation, the following observations were made: I. Load levels normalized post-traffic spike, yet users persist in experiencing high latency. II. Both database queries from CloudSQL and image retrievals from Cloud Storage exhibit elevated latency. III. No alterations were made to the website coinciding with the latency surge. IV. User-facing error rates remain unchanged. Anticipating another traffic surge, which action should you take to mitigate potential latency issues?