Southern California welcomed a surge of moisture that forecasters say could be the first in a series of early March storms, including a potential atmospheric river.

Rain began falling in some coastal areas during the Wednesday morning rush hour, with the system then spreading slowly inland. “Steady rain” lingered in the evening hours into much of Los Angeles County, but overall rain totals were relatively low, according to the National Weather Service.

Sierra Madre city leaders issued an evacuation warning​ in anticipation of the upcoming weather event. The warning will be in effect until 6 a.m.