Use the predict operator to understand future trends based on your existing data.
Search your Labs/Apache/Access logs looking for status_code 404 for the last 60 minutes.
Slice your 60 minutes by 1-minute increments and count your 404 status codes by timeslice.
Predict your future trend of 404s in 1 minute increments and plot results on a line graph.
| timeslice 1m
| count(status_code) as error_count by _timeslice
| predict error_count by 1m