[Gordis]

Originally Posted by ainur

The hobbits reached Bombadil's house on the 26th in the evening and stayed through the 27th, leaving on the 28th in the morning.

Originally Posted by radagastly

I am still convinced that Goldberry's "washing day" was more than just a coincidental rain. I also believe that the reason that Tom Bombadil kept the Hobbits in his house for an extra day was because he knew that they would be in more danger if he let them go while the Witch-King of Angmar was still prowling the Old Forest and the Barrow Downs.

I completely agree with you. Tom must have known that the Witch-King was visiting the Wights in the Barrows and kept the hobbits in his house for an extra day to let the WK finish his business and depart. To prove it we now have new quotes from the Hunt For the Ring published in the Reader's Companion:

" four of the Riders pursue Rangers along Greenway, and having slain them or driven them off Eastwards, make a camp at Andrath [...] [The Witch-king] now visits the Barrowdowns and stops there some days (probably until late on 27). This proves a main error, though in fact it was nearly successful, since the Barrowwights are roused, and all things of evil spirit hostile to Elves and Men are on the watch with malice in the Old Forest and on the Barrowdowns. RC, p. 145

Moreover, on September 27 there was an additional danger lurking around : two nazgul were unsuccessfuly searching for the WK somewhere on the Downs:

[Khamûl sends] sends [two nazgul] along the East Road, with orders to report to [the Witch-king] the eastward movement of the Ring [...][The two sent east] pass along the East Road, and visit Bree and 'The Prancing Pony'. They then go in search of [the Witch-king] but cannot at once find him [until 27th September]. - RC, p.164

So on September 27 (Goldberry's washing day) the Witch King was visiting the Wights in their Barrows, two wet and miserable nazgul were wandering on the Downs, and Tom kept the hobbits cozy and dry in his house. On the night of Sept. 27-28, the 3 nazgul, after a happy reunion, left together for Andrath, and the following morning (Sept 28) Tom bid the Hobbits farewell.