A flat shortwave trough will bring light rain to northern areas Saturday before the pattern turns highly active Monday night into Tuesday, with confidence remaining high for a major mountain snow event and potential valley snow chances later in the week.
The weekend will see gradual warming as a moist band shifts northward Saturday night through Sunday as a warm front ahead of a Pacific upper low approaching the California coast. Saturday will be mostly cloudy with highs near 56 degrees, while Sunday becomes gradually sunnier with temperatures reaching 58 degrees as southerly flow develops ahead of the approaching system.
The main event begins Monday as weather models continue showing remarkable consistency across multiple runs and ensemble suites. As the low off the California coast fills in and rejoins the main atmospheric flow, another low digging down the coast will help sling it over the area. The heaviest precipitation window remains Monday 5 p.m. through Tuesday 11 a.m., with precipitation chances rapidly increasing through Monday and reaching 50 to 95% by Monday night, highest over the mountains…