Ceilometer CL31 and CL51 for Meteorology Automated backscatter profiling captures detailed measurements on cloud base height and vertical visibility for multiple cloud layers — even in harsh conditions. Accuracy in all conditions Accuracy in all conditions Vaisala ceilometers accurately measure ceiling or base height of cloud layers, and they leverage pulsed diode lidar technology and single lens optics. They are engineered to deliver highly accurate data on multiple cloud layers even when conditions limit physical visibility. The CL31 model detects three cloud layers simultaneously to a range of 7.6 km (25,000 ft) and generates a full scope of measurements including precise assessment of inversion layers and nocturnal stable layers below 200 meters (650 ft). The CL51 model is designed for high-range, cirrus cloud height profiling that also includes detailed data on low and middle layer clouds as well as vertical visibility. It has a detection range up to 15 km (49,200 ft). FULLY AUTOMATED, 24/7 OPERATION FULLY AUTOMATED, 24/7 OPERATION Built to deliver in all conditions — even in extreme weather — the ceilometers provide data protected by backup battery, comprehensive self-diagnostics with contamination monitoring, and status reporting. Sensor reliability is boosted by optical filters for solar defense and tiltable automatic window blower with heater. EXCEPTIONAL DETECTION EXCEPTIONAL DETECTION Even when physical visibility is limited, the CL31 detects three cloud layers simultaneously and generates a full range of measurements including precise assessment of inversion layers and nocturnal stable layers below 200 m (650 ft). The CL51 also detects three cloud layers simultaneously — including the detection of Cirrus clouds — even under the most demanding conditions. RELIABILITY FROM GROUND UP RELIABILITY FROM GROUND UP Enhanced single lens technology allows Vaisala ceilometers to deliver highly accurate data on multiple cloud layers with a strong, stable signal over their full measurement range. The CL31 detects from ground-level fog to a vertical ceiling of 7.6 km (25,000 ft), while the CL51 has a full cloud reporting range up to 13 km (43,000 ft) and backscatter profiling over full range up to 15 km (49,200 ft). AFFORDABLE OWNERSHIP AFFORDABLE OWNERSHIP Nominal maintenance requirements and low operational costs are driven by extensive self-diagnostics, automated field adjustments and the practical modularity of engineering built into the Vaisala ceilometers. Resources Product Spotlight Ceilometer CL31 Capture accurate, reliable cloud base height, and vertical visibility data on multiple cloud layers to 25,000 feet (7.6 km). Download PDF Product Spotlight Ceilometer CL51 Explore high-range cirrus cloud height detection with a range up to 15 km (49,200 ft). Download PDF Industry Applications General CL31 & CL51 Information Get to know Ceilometers CL31 and CL51 and how they deliver fast, accurate cloud and visibility detection for a range of applications. LEARN MORE Aviation Applications Dramatically improve airport operations, flight safety, and operational continuity with full atmospheric awareness. LEARN MORE Urban & Industrial Systems Applications Enable full situational awareness and improved decision-making today’s urban and industrial settings. LEARN MORE Get started with Ceilometer CL Series today Contact Vaisala to learn how you can tackle the specific challenges of cloud height and mixing layer height measurement — especially for low clouds and low inversion layers, precipitation, and fog. Get comprehensive, actionable understanding of meteorological conditions, exactly when you need it. CONTACT US