1 Kikkerland Storm Glass Liquid Thunderstorm Storm Weather Barometer Predictor This storm glass measures: 5.5 H predicts thunderstorms snow rain overcast skies fog and wind. It is believed that electromagnetic changes in weather patterns activate crystals inside sealed glass chamber fills with crystals when air pressure decrease. The white flakes within the glass tube will change based on the barometric pressure which can be used to make predictions on what the weather will be. As the pressure changes it affects the chemical reaction taking place within the storm glass altering it. Clear liquid: fair weather Murky liquid: Rainy Crystals at top: thunderstorms Large flaky crystal: cloudy skies snow in winter Thread of crystals: windy weather