In this view looking south from Highway 38 above Forest Falls, a deep marine layer has flowed inland from the Pacific Ocean and become trapped beneath a temperature inversion, creating a broad blanket of low clouds that completely fills the valleys below while the higher peaks remain in brilliant sunshine. During calm winter conditions, cool, moist ocean air often advances through the Inland Empire overnight, spilling into lower elevations where it is unable to rise through the warmer air above, producing the dramatic “sea of clouds” effect seen here. The San Bernardino Mountains act as a natural barrier, with ridges and summits emerging like islands above the cloud deck, while the textured tops of the stratocumulus clouds reveal subtle air currents moving through the basin. As daytime heating strengthens, this marine layer typically begins to thin and retreat back toward the coast, but on stable winter mornings it can persist for hours, creating one of Southern California’s most spectacular mountain vistas.
