One of the benefits of War Caster is:
You have advantage on Constitution saving throws that you make to maintain your concentration on a spell when you take damage.
The spell Sleet Storm doesn’t deal damage, but the game designers still wanted it to make characters in the AOE make a CON save to keep Concentration. So it states:
If a creature is concentrating in the spell’s area, the creature must make a successful Constitution saving throw against your spell save DC or lose Concentration.
I definitely don’t think this is an intended interaction, but RAW, shouldn’t War Caster be useless for this since it says "when you take damage", and Sleet Storm is not a damage dealing spell?