File:Snow over California Fires (MODIS 2020-11-12).jpg

English: After a blistering-hot summer filled with drought and a ferocious fire season resulting in more than 4 million acres burned, the state of California felt the first hint of relief as substantial snow and rain fell in early November. On November 8, the National Weather Service warned of severe weather across the Sierra Nevada mountains, expecting 2-7 inches of snow to drop in the first snowfall of the winter. They also issued a freeze warning for the Sacramento Valley on that same day.

On November 9, 2020, the Moderate Resolution Imaging Spectroradiometer (MODIS) on board NASA’s Terra satellite acquired a true-color image of a fresh blanket of snow across the Sierra Nevada Mountains. In a refreshing change of pace, the eight red hot spots (each marking an actively burning fire) seen on the Terra MODIS image on November 5 were no longer detected and —for the first time in months—this section of the Sierra Nevada appeared free of smoke.

The NASA Worldview App makes it easy to view roll-over comparisons of images acquired by the MODIS instrument over the same area on different days. To view the change between an image of the Sierra Nevada by Terra’s Modis on November 5 and November 9, click here.

While the fresh snow and chilly temperatures have been helpful in fire suppression efforts, the fires have not been put out entirely. According to the U.S.D.A Creek Fire Morning Update published on November 10, the winter storm had dumped up to a foot of snow in parts of the High Sierras. Although the morning brought clear skies, the temperatures overnight had dipped into the single digits. The snow, which fell at areas above 4,000 feet on November 9, was accompanied by an inch of rain at lower elevations. While it suppressed fire activity, the snow and cold temperatures also brought dangerous driving conditions, making it difficult for firefighters to reach some areas. Aerial reconnaissance flights with infrared equipment confirmed lingering heat and smoke in the northeast corner of the Creek Fire. The Incident Fire Behavior Analyst, Bryon Kimball, was quoted as saying “A foot of snow is nice, but it’s not that much precipitation, maybe an inch. Until we get 5 or 6 inches of (precipitation) and get that moisture to penetrate those heavy fuels, we’re going to see smoke produced. At this point, it’s just a matter of letting those heavy fuels burn out.”

As of November 11, the Creek Fire has burned 379,802 acres and is reported at 70% contained. When viewing the November 5 image on NASA Worldview App, the Creek Fire can be seen as the largest red thermal anomaly (hot spot) that gives rise to copious gray smoke blowing westward and down the west slope of the Sierra Nevada.

The NASA Worldview app provides a satellite's perspective of the planet as it looks today and as it has in the past through daily satellite images. Worldview is part of NASA’s Earth Observing System Data and Information System. EOSDIS makes the agency's large repository of data accessible and freely available to the public.