Precise precipitation data for all types of precipitation
The Laser Precipitation Monitor (LPM) is the classic among distrometers: mature, robust, on the market for more than 20 years and available in many variants for various system requirements and applications. The LPM not only supplies data on precipitation intensity, but also provides detailed information on the type of precipitation.
- rain
- drizzle
- hail
- snow
- sleet
- mixed precipitation

Picture: Laser precipitation monitor, LPM: The monitor is equipped with heating elements. For extremely icy locations, the version with extended heating is available (not shown here).
LPM in use worldwide in various climate zones
Measuring principle
Based on the Gunn-Kinzer diagram, the type of precipitation is determined from the size and falling speed of individual particles. In this way, rain, drizzle, sleet, snow, hail and mixed precipitation can be distinguished from each other. While snow, for example, trickles down slowly, hail has the highest fall velocity. This proven method is now used in numerous national measurement networks around the world.
The LPM uses a laser-optical system that generates a parallel beam of light (infrared, 785 nm) that is interrupted by falling precipitation particles. A photodiode on the receiver side converts the interruption of the light beam into electrical signals, allowing the system to analyze the precipitation.
Data output and interface
The device provides an RS485/RS422 interface for data transmission. It includes two digital outputs (optocouplers) for pulse and status signals of the precipitation. Optional Ethernet interface.
Applications
The LPM is used in weather networks, meteorological and climatological research, hydrology and control systems for infrastructures. The LPM is used in transportation (road weather information systems) as well as in aviation and shipping. The device is used in almost all climate zones and in numerous applications. There are also a number of special applications, such as monitoring and classifying volcanic activity, environmental monitoring in the field of wind turbines and precipitation measurement in laboratory environments, for example in simulation systems for autonomous driving.
Additional features
The monitor is equipped with heating elements to ensure ice-free operation and measurement capability even in extreme weather conditions. It is robust and designed for reliable operation in various environments.
Want to find out more about the device?
You can find the technical details in our web product database - Laser Precipitation Monitor
Download our LPM product flyer
Request a quote: info@thiesclima.
LNM/LPM News: Reference News
Road Weather Application
Do you need more precise information on precipitation?
Then we recommend the 3D Stereo Disdrometer (5.412x.xx.xxx). The 3D Stereo Disdrometer evaluates camera images of precipitation particles using real-time image processing techniques and provides the user with the images of the precipitation particles. In this way, precipitation types can be fully and unequivocally documented. With this technology, precipitation types can be clearly identified regardless of the fall speed and particle size. Particularly in the area of solid precipitation, the method enables a very precise determination of water equivalents, i.e. the intensity and quantity of precipitation. False-positive signals due to insects and spiders are also detected and the measurement results are corrected accordingly.

Picture: 3D Stereo Disdrometer
Get to know other precipitation measuring instruments from Thies CLIMA:
Our models from the standard program:
3D Stereo Disdrometer, precipitation data incl. images of precipitation particles
Precipitation analyzerfor detecting supercooled components in precipitation events (FZRA, FZDZ, FZFG), as well as black ice formation and freezing spray
Clima Sensor US , fully integrated weather station with precipitation type detection
Precipitation Transmitter , tipping bucket principle
Precipitation monitor , precipitation yes/no (based on light barrier)
Rain sensor , precipitation intensity (based on light barrier)
Rain monitor, precipitation yes/no (based on capacitive sensor surface)
More details in the product database-overview
Precipitation analyzerfor detecting supercooled components in precipitation events (FZRA, FZDZ, FZFG), as well as black ice formation and freezing spray
Clima Sensor US , fully integrated weather station with precipitation type detection
Precipitation Transmitter , tipping bucket principle
Precipitation monitor , precipitation yes/no (based on light barrier)
Rain sensor , precipitation intensity (based on light barrier)
Rain monitor, precipitation yes/no (based on capacitive sensor surface)
More details in the product database-overview