GRAMMAR DETAIL

〜に限って

of all times · just when

Emphasizes that an unexpectedly bad event occurs on one particular occasion.

Examples

大事な日に限って、目覚まし時計が鳴らなかった。

Of all days, my alarm clock failed to ring on an important one.

急いでいる日に限って、電車が遅れる。

The train always runs late just when I am in a hurry.

傘を持たない日に限って雨が降る。

Of all days, it rains on the days when I do not bring an umbrella.

Structure: に限って after a time expression emphasizes frustration or surprise that something contrary to expectation happens just then.
Basic usage: 急いでいる日に限って、電車が遅れる。 expresses frustration at trains being late precisely on days when one is in a hurry.

Unfortunate timing versus limiting application
- 今日に限って電車が遅い expresses surprise that the train is late today of all days. 今日に限り半額です limits a discount to today, so the example's に限って differs in purpose from に限り in an announcement.