Two short lines of observation, and a feeling that something is about to go wrong. The scene is simple: ice at midday, when you would expect warmth and brightness. Instead the speaker says "I expect spoil," meaning decay, damage, or ruin. The ice isn't a pleasant winter sight here. It feels like a warning.
The second pair of lines shifts to light. It's white, which might suggest purity or hope, but the poem takes that away quickly. The light is "far and cold," like something you can see but not reach or be warmed by. The title, "Stroke," adds weight. It could point to a sudden blow, a touch, or a medical event, and the poem doesn't say which. Judging by the title and the mood, the speaker seems braced for a loss. The overall feeling is hushed, wary, and bleak, with very few words doing the work.