Cloud identification

The following time lapse video was captured and created using "Skyflow," an Apple iOS app running on my Apple iPad mini 6. The video — ~5 seconds long — was created from 151 frames stored in the "Files" app (Files / On My iPad / Skyflow / Projects). The photos were recorded from ~2:09 p.m. (14:09) to ~2:14 p.m. (14:14) using a two-second interval; each photo is 1.4 MB.

The video shows the sky over Fairfax County, Virginia USA during the afternoon of 17 February 2026. Can you identify the small, white puffy cottonball-like clouds shown in the video?

17 February 2026. Facing south-southwest.

Levels

Begin by trying to determine the "level" of the clouds. According to the International Cloud Atlas, there are three levels of clouds in the atmosphere (as shown in the following table): high; middle; and low. [Note: "Clouds with vertical development" is a fourth level used by some experts.] Since my home is located in the northern mid-latitudes, the column labeled "Temperate region" is highlighted by a red rectangle.

Source Credit: Levels | International Cloud Atlas.

"Sky Condition" - cloud amount and height

OK, let's assume you think the level of the clouds shown in the video is "High." Is there information available to confirm your inference?

When the height of a particular cloud is known, the concept of levels may be of some help to the observer in identifying the cloud. Source Credit: Levels | International Cloud Atlas.

Weather observations, sometimes automated, are available online (updated every hour) for select locations (often major airports) in the United States of America. For example Weather observations for the past three days for Washington/Reagan National Airport, DC is available for KDCA, the airport nearest my home. The following graphic shows the weather observations for KDCA nearest the date and times when I recorded the time lapse video (shown above). The column labeled "Sky Cond." is highlighted by a red rectangle.

Source Credit: KDCA | National Weather Service.

"Sky Condition" is reported for cloud amount and height.

Sky condition shall be coded in the format XXXYYY where XXX is the cloud amount code (e.g. FEW or BKN) and YYY its height above surface using 3 figures. Source Credit: METAR explanation.

The following table shows the codes used to estimate the cloud amount.

Source Credit: METAR explanation.

On 17 February, the "Sky Condition" is reported as "BKN210" for both times shown in the excerpt from the table of three-day observations for KDCA, meaning the cloud amount was "Broken" (5/8 to 7/8 of sky coverage) and the cloud height was "21,000" feet. At a height of 21,000 feet the cloud level is "High," meaning your inference is correct.

Now ask yourself, which High cloud "Genera" most closely matches the clouds shown in the video — Cirrus, Cirrocumulus, or Cirrostratus? That's right, the small, white puffy cottonball-like clouds shown in the video are Cirrocumulus clouds (Cc).

Tech Tips

How can you find near-real-time weather observations for your location? Use a table of three-letter LOCIDs (location identifiers) to find the nearest airport. For example, LAX is one of the airports near Los Angeles, California USA. Add the letter "K" in front of LAX and you get "KLAX." Take the Web address I provided for KDCA and change it as follows ...

https://forecast.weather.gov/data/obhistory/KLAX.html

This URL will take you to Weather observations for the past three days for Los Angeles, Los Angeles International Airport. The table is dynamic, meaning it is updated automatically every hour. (You might need to reload the page in order to get the latest observations.)

Deja vu

Did you notice the jet airplane that's visible in the last six frames of the video, moving from right to left across the screen beginning near the middle-right edge of the frame? That reminds me of "Sub-sensory imagery," a blog post I published in early January 2026.

My good friend Luis Acosta commented on aircraft condensation trails (contrails) that are also visible in the video. The contrails are probably higher than the cirrocumulus clouds.

Related Resources

• Weather observations for the past three days for Washington/Reagan National Airport, DC | NOAA NWS
• Weather observations for the past three days for Washington/Dulles International Airport, DC | NOAA NWS
• METAR explanation | IVAO Documentation Library - see section entitled "Cloud layers/Cloud amount and height"
• United States Airport Codes : Three Letter US Airport Codes [third party resource]
• Weather instruments at KDCA - Google Search
• National Weather Service Glossary
• Ten Basic Clouds | National Oceanic and Atmospheric Administration
• Introduction to Clouds / Sky Watcher Chart | NOAA NASA [PDF]
• Cloud Types | Center for Science Education | UCAR
• Module 4 - Cloud Identification | UW-Madison

Copyright © 2026 by Walter Sanford. All rights reserved.