September 20th, 2026 Timelapse
On September 20th, the day began under a complete blanket of low clouds, with visibility limited by an impressive 100% cloud cover. Surface winds barely stirred, averaging just 2.4 mph, while winds at 100 meters were slightly stronger at 3.3 mph. This minimal wind at the lower levels was not enough to induce much movement in the thick cloud cover, leaving the sky a steady gray. The temperature hovered around a cool 53.2°F, contributing to the damp, overcast atmosphere. With no precipitation reported, it seemed the clouds were merely a soft barrier, absorbing moisture without releasing it. The tranquility at the surface contrasted sharply with any potential turbulence aloft, where the wind dynamics could have created a slight shearing effect as the winds varied just enough in strength to keep those low clouds in place.
As the day progressed into midday, the atmosphere began to show signs of change. Surface winds picked up slightly to an average of 4.0 mph, while winds at 100 meters increased to 5.3 mph. This gradual intensification helped to break up the monotony of the morning cloud cover, reducing it to an average of 31.5%. The low clouds began to thin, allowing for brief glimpses of blue sky to emerge, a delightful visual contrast against the remaining gray. The increased wind speed suggested a more robust atmospheric mixing occurring, pulling the lower clouds upwards and causing them to drift more rapidly. While no mid or high clouds were present, the interaction between these wind layers hinted at potential turbulence, creating lighter patches in the cloud cover that danced across the sky as they shifted direction, showcasing the dynamic nature of the weather.
In the evening, the transformation was striking as the clouds nearly vanished, leaving just 0.2% cloud cover and allowing the sun to fully assert its presence. Surface winds increased slightly to 4.7 mph, while winds at 100 meters surged to 7.4 mph, creating a noticeable upward draft that further dispersed any remaining clouds. As the temperature rose to a warm 70.2°F, the environment felt decidedly more pleasant, shifting from the cool dampness of the morning to a comfortable warmth. The absence of cloud cover and the steady evening breezes created a serene atmosphere, while the differing wind speeds at various altitudes continued to indicate ongoing turbulence, albeit less visibly as the sky cleared. The day had evolved from a muted, cloud-covered morning into a bright, open evening, illustrating the ever-changing and fascinating nature of the Northwest skies.
September 20th, 2026 Timeline
Screenshots with weather data (wind layers, clouds, precipitation)
Weather Info for September 20th, 2026
Sunset: 7:13 PM