On the heels of all those lousy ISM reports, comes another poor harbinger: FedEx's earnings warning.

FedEx said it expects per-share earnings of $1.37 to $1.43 in its fiscal first quarter, which ended Aug. 31, compared with its June forecast of $1.45 to $1.60.

Shares are down only about 3% premarket, at $85.00. But the warning is more of...