This Ability effect may be in need of research. Reason:If a Sunshine Form Cherrim acquires a Utility Umbrella, does it revert to Overcast Form, or does it remain stuck in Sunshine Form regardless of weather? Does it affect both moves used by the user and moves used targeting the user, or just one of the two (e.g. Fire-type moves in harsh sunlight, Blizzard in hail, etc.)? Does it prevent Sliggoo from evolving? If a Pokémon holds a Utility Umbrella, is it unaffected by its ally's Flower Gift? Does it bypass Sand Stream's Sp. Def buff? You can discuss this on the talk page.
The Pokémon holding Utility Umbrella is unaffected by effects of weather.
The holder's moves and Abilities that are affected by weather behave as if there was no weather present. For example, the holder's Weather Ball will be Normal-type and its power will not be doubled.
Overcast Form Cherrim holding a Utility Umbrella cannot change to Sunshine Form.
Ice Face is not affected by the Utility Umbrella; if hail starts, Noice Face Eiscue holding a Utility Umbrella will still change to Ice Face Eiscue.