Vidensdatabase

These indicators appear when pre-treatment or post-treatment is not recommended based on the event’s setup and pavement conditions.

• N/A (N/A):
  This means conditions do not support an effective pre-treat or post-treat. In these cases, temperatures, timing, or pavement conditions would make treatment ineffective or unnecessary, so applying material would not improve safety or performance.

• N/A (Rain):
  This occurs when rain is expected before wintry weather. Steady or heavy rainfall can wash the deicing application off the pavement before it has any chance to work, leaving little to no benefit. Because the deicing application would be largely lost, and its effectiveness greatly reduced, the system flags pretreatment as not recommended.

• N/A (Wind):
  This applies to dry snow events, typically with a 15:1 snow-to-liquid ratio, combined with high winds over 25 mph that cause blowing or drifting. In this setup, snow often blows across an untreated surface without sticking. However, when a deicing application is applied, that chemical layer can actually catch the blowing snow and cause it to bind to the pavement, creating a layer of snow or ice. Since treatment can make conditions worse in this scenario, the system identifies pre-treat or post-treat as not advised. Here’s a video demonstrating this scenario: https://www.youtube.com/watch?v=0rL37Yd1X6o

In short, you’re still getting snowfall timing and accumulation details, but when any of these N/A indicators appear, the system is signaling that the safest and most effective approach is to avoid pre-treating or post-treating for that specific event. In some cases, a deicing application may still be applied closer to the transition to wintry weather, it is simply not recommended prior to the start of the event.