Ceilometer CL31 & CL51 Fast, accurate cloud and visibility detection for a range of applications. Accurate cloud measurement, improved operations Reliable cloud and visibility detection is crucial for modern forecasting, situational awareness, and air quality reporting. Compact, lightweight, and built on trusted Vaisala technology, CL31 and CL51 ceilometers are the ideal choices for assessing the boundary layer, cloud ceiling and base height, and more.These globally recognized and trusted sensors provide crucial benefits for a wide range of applications:Excellent performance in all weather conditions, with consistent measurement accuracy down to nearly ground levelFully automated, 24/7 operation, with optical filters for solar defense and a tiltable automatic window blower with heaterExceptional detection that avoids pitfalls of dual-lens optics and provides reliable results at all heightsSimple installation and maintenance, with low operational costs, extensive self-diagnostics, automated field adjustments, and design modularityConvenient visualizations and actionable insights, including an automatic algorithm for online retrieval Which model is right for you? 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). Industry Applications Aviation Applications Dramatically improve airport operations, flight safety, and operational continuity with full atmospheric awareness. LEARN MORE Meteorology Applications Create more accurate forecasting and environmental awareness, protecting people and communities. LEARN MORE Urban & Industrial Systems Applications Enable full situational awareness and improved decision-making today’s urban and industrial settings. LEARN MORE Resources Datasheet Ceilometer CL31 See technical data for this compact and lightweight instrument for cloud base height and vertical visibility measurements. Download PDF Datasheet Ceilometer CL51 Get more detail about how CL51 measures high‑range cirrus cloud heights in harsh conditions. Download PDF ADDITIONAL RESOURCES Access additional information about CL31 and CL51 Find additional resources, applications and information about CL31 and CL51 here. ADDITIONAL RESOURCES Get Started with Ceilometer CL31 & CL51 By making the CL31 or CL51 the foundation of your atmospheric awareness, you can dramatically improve your operations and decision-making. Contact us now to see which technology is right for you. CONTACT US