The speaker pictures himself as a kind of god, drifting over his homeland not in person but through weather maps. Home has become something seen from a great height: a patch of haze, an evening high-pressure system. The poem treats these forecasts almost tenderly, giving the country a "her," as if the land were someone he loves and watches from afar.
The last lines turn quietly strange. Something "pretty," like a colorful map or a gentle sunset, gets translated into "the impossible." That could mean the beauty of the place is too large or too distant to hold, or that reducing a real country to symbols makes it feel unreachable. The speaker seems wistful, maybe homesick, and a little detached. The mood is calm and hushed, but there's an ache underneath it. Being godlike here doesn't feel powerful. It feels lonely, like knowing everything about a place from the outside while not being able to touch it.