Measuring sky conditions since 2008
The high-precision, low-cost system for monitoring weather conditions and measuring sky quality for your remote observatory. Now with sky-quality grade light sensor included at no extra cost.
Four sensors as standard, two optional. Everything you need to know whether your observatory should be open or closed.
Infrared sky temperature measurement to detect cloud cover in real time.
Capacitive or Hydreon optical version. Immediate detection of any precipitation.
Measures sky darkness in mpsas (magnitudes per square arcsecond). Included at no extra cost since 2023.
Ambient temperature reading to help interpret sky conditions and dew risk.
Atmospheric pressure and relative humidity sensor with improved accuracy. Available as an upgrade.
Calibrated industrial wind speed sensor, rated to 180 km/h. Protects your telescope from strong winds.
Thousands of observatories around the world trust CloudWatcher to protect their equipment night after night. See how amateur and professional astronomers use it in their setups.
CloudWatchers in the Wild
Over fifteen years of continuous improvement, driven by the people who use it daily.
Clouds, rain, sky brightness and temperature, all in a single device, with clear graphs and easy-to-read displays.
Measures sky darkness with a high-sensitivity light sensor, the same reading used by professional sky quality meters, now included at no extra cost.
Safety monitor and observing conditions ASCOM drivers included. Compatible with N.I.N.A., Voyager, MaximDL, ACP, SGPro, CCDCommander and more.
Free Windows software, INDILib and INDIGO support (Linux/Mac), plus a paid 3rd party macOS app. Updated continuously since 2008.
Robust design with minimal moving parts. Long-standing owners can also fit upgrades such as a lid with the latest rain sensor, or an atmospheric pressure and relative humidity sensor. Our repair and spare parts price list is an attractive alternative to buying a brand new device.
Thousands of observatories protected worldwide. Read how other observers use CloudWatcher to keep their equipment safe, in CloudWatchers in the wild.
Free software for all major platforms, with ASCOM drivers and compatibility with the most popular observatory automation programs.
The CloudWatcher software runs on Windows, macOS and Linux. The mobile app keeps you informed wherever you are, with instant alerts when conditions change.
The SOLO makes the CloudWatcher available 24/7, independently of a connected PC. It reads the CloudWatcher sensors and acts autonomously, ideal for remote observatories where a computer may not always be running.
With an Android widget available for at-a-glance status from your phone.
Discover The SOLO →
Need a portable cloud and sky quality detector? The PocketCW2 is a compact device with its own free app. No observatory required.
| Power supply | 12V or 15V DC, <1 A |
| Communication | RS232 serial port |
| Connectors | IP68 weatherproof |
| Dimensions | 110 × 85 × 37 mm |
| Cable length | 3, 5, 7 or 10 m (choose at order) |
| Max. cable + extension | Up to 30 m |
| Relay voltage | Up to 220 V (12–24 V recommended) |
| Standard sensors | Clouds, rain, sky quality, temperature |
| Optional sensors | Pressure, humidity, anemometer |
| Sky quality unit | mpsas (mag/arcsec²) |
| Wind sensor rating | Up to 180 km/h |
| Rain sensor options | Capacitive or Hydreon RG-9 |
| Firmware updates | User-updatable |
| In production since | 2008 |
The IP68 connector cable can be routed through conduit: the cylindrical connector is only 19 mm in diameter, making installation straightforward.
Extensions available in the same lengths (3, 5, 7, 10 m) for a total reach of up to 30 m.
