What is ClearPath Weather®?

A suite of weather products that provides decision makers with multiple ways for effectively managing inclement weather and road issues before, during, and after weather events.

Each ClearPath Weather® forecast provides hourly current and forecasted site-specific road and weather conditions for:

  • Pavement/Bridge temperature
  • Pavement/Bridge condition
  • Pavement/Bridge frost risk (%)
  • Route-specific treatment recommendations
  • Wind speed and direction
  • Visibility and obstructions
  • Precipitation type, rate, and accumulations
  • Snow accumulations

What Makes the ClearPath Weather® Forecast Different?

Most weather providers like the NWS deliver just a weather forecast.

Iteris provides a route-specific detailed hour-by-hour pavement and weather forecast that is updated at least hourly.

Giving that extra level of detail that is needed to make effective maintenance decisions.

What is HiCAPS?

HiCAPS stands for Highway Condition Analysis and Prediction System (HiCAPS). This was developed by Iteris (formerly Meridian Environmental Technology) and is the industries only model to take into account BOTH Energy and Mass. This means that when moisture (as snow, rain, frost, dew) is deposited onto the road it also transfers energy to or from the road, and that evaporation and/or sublimation of moisture from the road requires the road to have an adequate amount of energy available to support those processes.

When that phase change does occur a loss or gain in heat can occur, therefore this is modeled within our pavement model and can directly affect the pavement condition as well.

HiCAPS takes into account past and forecast weather data, solar radiation, ground temperatures, run-off, wind effects (blowing snow off of the road), traffic, and so on. We then incorporate algorithms that we have in place that represent pavement or bridge (asphalt and concrete) behavior and model how the change in weather variables will impact the pavement/bridge. We also use local RWIS data, if available, and provide a weighted average of this data to help drive the model.

How do we make a pavement forecast without pavement observations?

While the local RWIS data helps us provide as accurate a pavement or deck forecast as possible, the model is actually built to be able to provide a forecast in the absence of pavement temperature input data as well. If an RWIS station experiences an outage of pavement data, we still want to be able to provide a forecast. Also, some comparative research we've done with HiCAPS has shown that we can achieve nearly the same results without having pavement temperature input as we can when it's available. This is because there's a brief spin up period the model uses that allows it to acclimate itself to the environment in which the starting pavement temperature is only a very small part. The influences of ground temperature, radiation, precipitation, etc force the pavement model in a similar direction regardless of what the pavement temperature was at the very start. The versatility of being able to still operate the model without actual RWIS pavement temperature input is very useful, as it ensures the forecast will always be available, and it allows users to choose forecast locations that aren't absolutely limited by the placement of RWIS stations.

Benefits of ClearPath Weather®:

  • Interactive web-based display
  • Provides quick and effective access to your preferred data
  • Pinpoint start/end times for precipitation
  • One-click menus
  • Map-based, graph, or table views
  • Looping radar to show a storm’s progress and track
  • 24/7 weather monitoring by road weather meteorologists
  • HiCAPS pavement forecasts
  • Custom mobile alerts