Road Weather Sensors & Surface Condition Monitoring

Optical present weather sensors like OSI's DSP-WIVIS use in-beam optical scintillation and off-axis forward scattering to measure how particles in the air interrupt and scatter an infrared LED beam. Different precipitation types — rain, snow, drizzle, freezing rain, hail — produce distinct scintillation and scatter signatures. Integrated temperature, humidity, and optional acoustic sensors further refine discrimination, allowing the system to report over 50 NWS/WMO weather codes accurately.

OSI road weather sensors measure meteorological optical range (MOR), which is the standard metric for visibility used in transportation and aviation safety. The sensors are designed to detect fog, haze, precipitation-induced visibility reduction, and clear conditions across the full operational range relevant to highway safety. No field calibration is required, and measurements are reported once per minute with instantaneous intensity updates every 10 seconds.

No. OSI sensors are engineered for unattended, maintenance-free operation. Automatic compensation for dust, water droplets, and ice or snow buildup on the optics eliminates the need for scheduled cleaning or field calibration. With an MTBF exceeding 80,000 hours and no moving parts, these sensors are ideal for remote highway installations where technician visits are infrequent or costly.

Yes. All OSI present weather and visibility sensors comply with NWS (National Weather Service) and WMO (World Meteorological Organization) weather code reporting standards. They output over 50 standardized weather codes covering rain, snow, drizzle, freezing precipitation, mixed conditions, and more. The FAA-certified OWI-430 family also meets FAA AWOS present weather requirements, making these sensors suitable for co-located airport and highway monitoring deployments.

Yes. The LP-WIVIS (OWI-650) is specifically designed for battery or solar-powered installations and features low power consumption with an intermittent operation mode. The OWI-432 small weather station and APG precipitation gauges are also solar compatible, running on nominal 12 VDC at a maximum of 400 mA. This makes them well-suited for remote highway segments, mountain passes, and other off-grid RWIS locations where AC power is unavailable.

Yes. OSI's HIPS (HIP-100) Hail and Ice Pellet Add-On Sensor uses acoustic detection technology to reliably discriminate solid ice particles — hail and ice pellets — from water droplets, a task that is difficult with optical methods alone. When combined with the OWI-430 or OWI-650 series sensors, the HIPS provides superior all-precipitation discrimination, which is especially valuable for highway safety monitoring and avalanche risk assessment in mountain corridors.