All snow and ice is not created equal. The term snow and ice cover can cause some confusion, as it may not mean what you think it means. Not all snow and ice on the ground is considered snow and ice cover.
Snow and Ice Cover
Snow and ice cover has a very specific definition, which is: snow and ice as a result of wintry precipitation on untreated, undisturbed and exposed outdoor surfaces. Basically, it is snow and ice from a winter weather event that is untouched by human activity. A sidewalk, driveway or street is normally not considered a surface that would be representative of snow and ice cover. Think of a large pile of snow in a parking lot. That snow and ice pile can remain months after a winter weather event occurred and after all snow and ice cover has melted away. That pile still exists because of a situation created by human activity. Therefore, it is important to note that any weather data or forensic weather report will only reference snow and ice cover that occurred due to an event.
As a result, this snow and ice cover definition can lead to some confusion and the false sense that no snow or ice was present at a location. There are a number of instances when snow and ice is present, even though no snow or ice cover is. The most common issue is leftover piles of snow and ice. Since piles of snow and ice are created by human activity, they often linger much longer than naturally occurring snow and ice cover.
Another common instance is black ice, which can form in a number of ways. Black ice is defined as a thin coating of ice that is clear and therefore appears as the same color of the surface it developed on (e.g., asphalt, macadam or black top). Black ice can form as a result of melting of snow and ice, which develops into ice after the temperatures fall back below freezing. This type of ice can also form after a plain rainfall event occurs and the temperature subsequently falls below freezing before surfaces have enough time to dry. The resulting ice in these situations will not be noted in weather data or in forensic weather reports as snow and ice cover.
These nuances within the weather data show the importance in using a Certified Consulting Meteorologist rather than just taking the weather data at face value. Without the assistance of a weather expert, you could be missing the complete picture of what happened.
Give CompuWeather a call at 1 (800) 825-4445. Speak with our Certified Consulting Meteorologists and see how their expertise can add value to your legal case or claim.