Opening Day attendance
Fewer fans than usual saw the Mariners home opener from inside T-Mobile Park.
The average attendance on Opening Day in Seattle is roughly 45,607. The recorded attendance for Thursday night's opener against the Athletics was 42,871, or about 6% fewer than average. It's the second lowest Opening Day attendance in a non-COVID year, just slightly higher than 2013.
To be clear, this doesn't matter. Attendance on Opening Day is not predictive of the Mariners full season attendance -- i.e., a low or high attendance in the first game of the year doesn't tell us much about whether fans will go later in the summer.
And attendance on Opening Day is not predictive of the Mariners year-end record, suggesting fans either don't know the the quality of the team at the beginning of the year, or that's not why they go.
The weather might have something to do with it. I assume a tornado advisory and lightning storm in the Seattle area on Wednesday kept some fans from heading to the ballpark on Thursday. But I don't see any obvious year-over-year relationship in the data, as the weather is almost always cold and bad in Seattle on Opening Day.
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