“viņi ieradās dažas dienas vēlāk” — they returned several days later (= after several days)
“kā viņš mirkli vēlāk pats nožēloja savas īdzīgās domas!” — as he himself a moment later regretted his crabby thoughts
“pirmdienas rīts atgadījās gluži tāds pats kā šodien, no sākuma miglains, vēlāk saule” — Monday morning the same happened as today, initially (it was) foggy, later (there was) sun