From wikipedia: The weather on Shemya is very drastic, though the temperatures only vary between single digits to the mid fifties, and the climate is perhaps the most equatorward low-altitude occurrence of a polar climate (ET) in the world, though it is extremely close to a subpolar oceanic climate (Cfc).
The island weather is most likely to be cloudy with a mist and the wind is often in the mid 30s to 40 mph.