Answer

The fourth stanza focuses more on the rain that is brought back in at the end of the third stanza.

‘pale rain over the dwindling harbour’
‘over the sea wet church the size of a snail’
this image is effective as it emphasises the size of the church, the grey colour and also the wet spray of the sea/rain over it, like a snail might glisten. The atmosphere is less pleasing now.

There is a reminder of summer, which has recently ended, but there is still the remnants of the gardens ‘blooming in the tall tales beyond the border’, but he is prevented from enjoying these now by the ‘weather turned around’

The weather is changeable, as in the fifth stanza it is ‘blue altered sky’ again, but he is also looking back in time at himself, as he can see ‘a child’s forgotten mornings when he walked with his mother through the parables of sunlight’