All-Sky imagery at Earth Modeling Branch: | Purpose | Gallery | Cases

The LAPS system ( is being used to produce rapid update, high resolution analyses and forecasts of clouds and weather. We are now producing realistic sky (and land) simulations from these weather analyses and forecasts. The 3-D cloud analysis, running over our Colorado 500 meter resolution domain uses satellite (including IR and 1-km resolution visible imagery, updated every 15-min), METARs, radar, aircraft and model first guess information to produce an hourly 3-D field of cloud fraction, cloud liquid, and cloud ice. The analysis is then converted using a ray-tracing technique into an all-sky image. Here are some links with more details in this seminar, this AMS presentation and this satellite conference poster. A recent ESRL news story on this work has been posted.

The image above on the left is simulated from the LAPS cloud analysis and other data, while the image on the right is from an all-sky camera maintained by the Earth Systems Research Laboratory at the same time. In each fisheye lens view the zenith is in the center and north is up. The color balance of the simulated image is set to reproduce the "actual" colors/radiances when the display white point is set to closely match the sun. Thus to see a true apples to apples comparison (if for example you take your computer outside or right by a window), please set your display to a color temperature of 5780K (the sun's white color above the atmosphere). Some images are shown a bit dark to avoid saturating and losing details on the bright end. This can be compensated for by turning up your monitor brightness, thus showing a broader dynamic range.

Select Site — DSRC | BAO Tower | Longmont Astronomical Society | Pikes Peak | Mount Evans

Latest all-sky comparison image | mask (site is DSRC)

Latest comparison animations (site is DSRC): Polar | Cylindrical

In these 360 degree panoramic views, the top is a simulated LAPS image and bottom is a remapped camera image from an all-sky camera maintained by the Earth Systems Research Laboratory. South is at the center of each image and north is at the edges.

Latest Simulated image | Latest Camera image | animation (site is DSRC) | Sample forecasts: (Kansas Storms) | (Moore Tornado)

Archive Directories (site is DSRC): Polar Comparison | Cylindrical Comparison | Cylindrical Simulated | Verification

Contact: Steve Albers (