gerund with compound clause for subject

Consider four sentences:

1. The reason I am late is bad weather.

2. The reason I am late is the weather being bad.

3. The reason I am late is the weather’s being bad.

4. The reason I am late is a very adverse sequence of meteorological events having occurred

Sentence (1) presents a rather plain case of "bad weather" identified as the cause of someone’s lateness. The clause takes the subjective case.

Sentences (2) and (3) present this cause as a gerund. Following a separate discussion over the subject of a gerund, both (2) and (3) are grammatical, though the former, which uses an accusative form of the subject "weather", is more informal than the latter, which uses a genitive form.

Taking a preference for (3) over (2) for some stylistic objective, how might one apply the same preference to (4), in which case the subject of the gerund is the compound clause "a very adverse sequence of meteorological events", which is not directly transferable to a genitive form?