More than one-third of an inch of rain fell in downtown Modesto early Sunday morning, and more is expected.
Forecasters with the National Weather Service predict more showers today as a slow-moving Pacific storm moves through Northern California.
The crackling of thunder could be heard throughout the Northern San Joaquin Valley early this morning.
Modesto has received .38 inches of rain since midnight, including neary a third of an inch from 2 a.m. to 4 a.m., according to the Modesto Irrigation District, which tracks rainfall from its downtown office.
Later today, as the center of a low pressure system moves closer to the coast, the atmosphere is expected to become unstable, bringing more thunder, brief heavy rain and possibly hail.
Rainfall could vary in some areas from a half-inch to an inch. Snow isn't expected below 7,000 feet.
The storm should move through by tonight, though there could be possible showers on Monday, forecasters said.
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