"Snow and Ice Forecast: How slippery will it be today?"
Winter weather brings not only cozy snowy landscapes but also dangers from slippery conditions. Understanding when and where it can become slippery is crucial for your safety on the road and as a pedestrian. The temperature alone is not always the decisive factor.
Types of Winter Slipperiness
There are several reasons why roads and sidewalks can become slippery:
- Snow Slipperiness: Caused by compacted snow or melting and refreezing snow. This is the most obvious form of slipperiness.
- Icy Slipperiness (Freezing Rain): Particularly dangerous. Rain falls onto frozen ground (below 0°C / 32°F) and freezes instantly into a sheet of ice. This can paralyze entire regions within minutes.
- Frost Slipperiness: Occurs on cold, clear nights when humidity freezes directly onto the cold road surface into ice crystals. It often appears surprisingly, even though it has not rained or snowed.
The greatest danger is so-called "black ice," a wafer-thin, transparent layer of ice that is barely visible on the dark road surface.
What to Look for in the Forecast
- Temperatures around freezing: The greatest risk of slipperiness often occurs not in deep frost, but at temperatures between +2°C and -3°C (36°F - 27°F). In this range, melting snow can easily refreeze.
- Precipitation and Ground Temperature: A forecast of rain with air temperatures around 1°C (34°F), but ground temperatures below 0°C (32°F), is a clear warning sign for icy conditions.
- Hourly Forecast: Pay attention to when the temperature drops below freezing. If it has rained before, expect refreezing wetness in the evening and night hours.
Particularly Dangerous Spots
Slipperiness does not occur uniformly everywhere. Be especially careful:
- On bridges and in depressions: Here, the road surface cools down faster than on the ground.
- In shaded forest sections: Here, ice thaws more slowly and can persist throughout the day.
- At intersections and in curves: Where there is a lot of braking and steering, the ice can become polished and mirror-smooth.
Tips for Your Safety
Plan more time for your journeys in winter. Drastically reduce your speed and avoid abrupt steering and braking maneuvers. As a pedestrian, shoes with good tread are essential. During an acute ice warning, it is safest to leave the car and stay at home if possible.