Interior valleys of California are often shrouded in dense fog at this time of the year as a low sun angle combined with short daylight hours prevent the fog from burning off.

About the only way for that fog to clear during a typical December is for strong winds to blow it away.

The hurricane-force Santa Ana winds on the first day of the month did just that. They also left humidities so low that the fog had not returned even by Saturday, December 3, 2011.

That’s when NASA’s Aqua satellite took the image to the right, revealing the varied and dramatic landscapes of the Golden State and neighboring Nevada.

The expansive Central Valley and its patchwork of farmland is entirely fog-free in the image, taken when the satellite passed overhead at midday.

The snow-capped spine of the Sierra Nevada can also be seen clearly standing out against the dark green conifer forests to the west and the Nevada desert landscape to the east.

Regular rainfall and temperate conditions during November have allowed a verdant terrain to emerge across the California Wine Country, north of San Francisco Bay.

The region’s hillsides and valleys are typically straw color during the rain-free summer and early fall season, usually not returning to such a deep shade of green until higher sun angles return in January.

Full story and image: NASA