Don't get it wet!

If there's rain outside, it's crucial to protect fascinators and hats from getting wet. This will help prevent any potential damage that could occur. It is especially important to keep sinamay and straw hats dry, even indoors, as they are more susceptible to melting or becoming misshapen when exposed to moisture.

Follow care instructions or ask the designer. To be absolutely safe, unless it's called a rain hat then don't get it wet.