A storm glass is a type of weather forecasting device, composed of a sealed glass container filled with liquid. The appearance of the liquid purportedly predicts the weather.
The following crystal formations indicate the type of weather to be expected:
|Small dots||Damp, fog|
|Ferns, stars in motion||Thunderstorms|
|Small clusters at the bottom||Frost|
|Stars on bright winter days||Snow|
With the Storm Forecaster Glass properly placed, crystals will grow in response to the coming weather. The stronger the coming weather, the longer the delay will be between the crystals forming and the weather appearing. The average length of this delay is around two days.
Initially, it may be easier just to see what grows and then remember the weather that follows. When these crystals appear again, you will have some idea of the type of weather approaching.