Detailed Instructions: Given a travel related situation, and given a specific question about the situation, summarize the question into a title
Problem:I happened to be looking at a flight from yesterday (as writing) which was drastically delayed...

https://flightaware.com/live/flight/UAL48 (choose "Sept 2")

Now, on the many excellent flight info sites, you can quickly determine if a flight is delayed.

But - is there a way to find out WHY that flight was delayed?

This becomes quite critical if you're on the same flight the next day!

(Indeed for that specific flight, I notice the next day's one is unfortunately already marked as going to be delayed many hours; now I wonder about the next day.)

If you can know why a delay happened, it would surely be useful info if you're on the following versions of a flight.

Is there a way to do this?

(Often if you just "call the airline and ask", the staff in reservations often really don't know specifically.)

The sense of my question is, "If you're on one of the next flights of that flight number, to try to find what the heck is going on...!"

Solution:
Find what caused a current big flight delay?