Rashi: It is the cold of days of snow. One desires this in the days of harvest (summer). It is not literally snow, for it is not good at harvest time!

Malbim: Just like on a day of harvest, the day burns like an oven and strikes the head of the harvester until he faints. If the cold of days of snow will come, it will revive him.

Malbim: If the king's and officers' anger flared against one, he is in danger to die via this. He sends someone faithful to advocate for him. He turns back the anger, and saves his master's life, just like cold revives one who fainted from heat. A messenger goes and returns and brings an answer to revive the fainting Nefesh who sent him.

Malbim (according to the metaphor): Every person is a messenger sent in this world. He must be faithful to his Sender, to do what he was sent for. Then he will return Nefesh Adonav - his Nefesh, which is a part of Elokim. Then, he will not fear the future flame that will burn like an oven; they will cool Gehinom for him, like Chazal said about "Bah Tashleg b'Tzalmon" (Tehilim 68:15).