Is it “freezing rain” in Hokkaido? Watch out for “freezing rain” –Weathernews

Although it has been snowing in many places in Hokkaido since last night, warm air began to flow from the south as the cyclone moved north, and many places changed from snow to rain.

In eastern Hokkaido, cold air was stored in the lower atmosphere, so even after hot air began to enter the sky, the earth’s surface temperature remained low.

Atmospheres at altitudes below 10,000 meters generally cool as they move higher in the sky. Some of this was reversed today, with temperatures below the coldest 1500 meters on the ground. This is a phenomenon called the inversion layer.

Therefore, it seems that the snow that fell from the sky melted in the middle and turned into rain, followed by the freezing process again near the surface of the earth, and ice particles fell as hail called “freezing rain”. The snow has a whitish appearance, but the ice granules are characterized by an almost transparent color.

If the warm air intake continues to progress after this, it is expected that the rain will not freeze completely and fall as drops of water close to the ground.

However, depending on the conditions, such as the temperature at the moment, the water droplets can fall into a state of “supercooling” in which they do not freeze even at 0 ° C or below, and in that case, they can freeze in the moment they touch. an object on the ground. This phenomenon is called “ice shower”. When glazing occurs, tree branches and the like are coated with transparent ice.

Although it is a beautiful phenomenon, if rain and ice fall on the cables, it can easily cause power outages or the road surface to freeze and slide easily.

Be aware that these phenomena can occur in the process of turning snow into rain.