Residents across Northern California can expect a significant shift in the weather beginning Wednesday, as the National Weather Service in Sacramento has forecast a series of storms that are poised to bring a range of impacts, from heavy rain and gusty winds to deep mountain snow. These conditions are expected to cause major travel disruptions throughout the end of the week, with a brief pause over the weekend before another system rolls in early next week, according to the NWS forecast discussion.
The first storm, hitting today through Thursday, ushers in widespread precipitation, fueled by an atmospheric river that's slated to bring enhanced precipitation rates, particularly in the Sierra and southern Cascades later in the day. Thunderstorm probabilities for today hover around 5 to 15 percent in the Sacramento Valley and neighboring foothills, then increase to 20 to 35 percent by Thursday afternoon and evening. Thunderstorms that develop may produce brief heavy rain, gusty winds, hail, lightning, and possibly a brief funnel cloud, according to the NWS. Winds are also forecast to gust between 40 to 55 mph across the Delta, Valley, and foothills, with the potential to reach 65 mph at higher elevations.
Precipitation chances range from 15 to 30 percent in the Delta and Valley for areas to receive more than an inch of rain, while the likelihood increases to 50 to 80 percent across the northern Sacramento Valley and foothills. Snow levels will begin at 4,500 to 5,500 feet today, dropping significantly by the evening, with heavy snow expected along the Sierra this afternoon and evening, impacting lower elevation regions as well. The heaviest precipitation is forecast for the Sierra and southern Cascades this afternoon and evening, and the timing of the snow level drop will significantly affect potential snowfall accumulation in lower elevations.
The second storm, expected between Friday and early Saturday, will bring additional precipitation, with snow levels around 2,000 to 3,000 feet. This suggests potential snowfall accumulation above 2,500 feet in the Sierra and parts of Shasta County. The likelihood of up to two inches of snow is estimated at 30 to 60 percent. While the Friday system is expected to move through quickly, it will be followed by Storm #3, which is forecast to occur from Sunday through Tuesday. This storm is expected to bring moderate precipitation, with a 20 to 50 percent chance of rain exceeding one inch in the Valley and foothills, and a 60 to 95 percent chance of snowfall surpassing 12 inches above 5,000 feet, as reported by the National Weather Service.
Transportation agencies and drivers are advised to stay alert as weather developments unfold. Experts recommend taking necessary precautions, preparing for potential impacts. With the first of these systems making landfall today, residents and travelers in the affected areas should be prepared for winter weather that may affect the region’s conditions into next week.
