Residents across San Diego should brace for a significant downpour as the National Weather Service predicts a surge of rainfall that could lead to urban flooding towards the end of the week. According to the NWS forecast, the region is expected to experience scattered showers increasing in coverage on Wednesday night, turning into the most widespread and heaviest rainfall from late Thursday into Friday morning. For those living in Orange and southwestern San Bernardino counties, rainfall may range from 2 to 4 inches near the coast, escalating to 4 to 8 inches in the mountains, with the greatest amounts on south-facing slopes.
While San Diegans prepare for the approaching storm, they have experienced warmer nights with gradually cooler days leading up to the storm, as the NWS noted a low-pressure system making its way southward off the coast. This same system, coming from the coast, is expected to sweep inland through southwestern California on Friday, triggering rainfall amounts of 2 to 3 inches for the coast and valleys and between 2 to 4 inches in the mountains for San Diego and western Riverside Counties. As reported by the Area Forecast Discussion, the low deserts could see around one inch of precipitation.
Taking a closer look at the daily conditions, today's weather will be cloudy with a 50% chance of showers and a high near 67 degrees, as indicated by the Detailed Forecast issued by the NWS. Winds shift from south to west in the afternoon, and rainfall amounts of less than a tenth inch are on the table. Evening forecasts call for similar conditions, with the chance of precipitation holding steady at 50% and overnight lows around 58 degrees.
As the week progresses, Thursday is set to bring showers and the possibility of thunderstorms after 10 a.m., adding to the potential hazards. Stronger south-to-southeast winds, with gusts as high as 25 mph, signal that the storm's peak may hit the region with full force. This brewing storm not only threatens to fill the streets but, as stated by the NWS, the San Diego River through Mission Valley might be flirting with flood conditions on Friday. High surf and strong rip currents are anticipated at the beaches leading up to the weekend, adding a dangerous edge to coastal areas grappling with the storm's impact.
Marine conditions are also set to deteriorate, with an increase in southerly winds possibly creating hazardous conditions from Wednesday night into Thursday. The Area Forecast Discussion forewarns of a slight chance of thunderstorms during this period, cautioning of erratic winds, lightning, and heavy rain that could significantly impair visibility at sea. By the time Christmas Day swings around, forecasts are calling for sunny skies with the storm having moved on, providing a stark contrast to the tumultuous weather conditions seen during the week.
