Residents across San Diego are experiencing warm, dry conditions that have persisted into the weekend, with Santa Ana winds bringing gusts up to 45 mph in some areas. According to the National Weather Service San Diego, the coastal mountain slopes and mountain passes are particularly affected by the winds, which have extended into the inland valleys below the passes, with gusts between 25-35 mph. High temperatures in the region are following an unusual trend, remaining above the average for this time of year.
Meanwhile, the forecast discussion from the National Weather Service revealed a shallow marine layer along the coast this morning, which quickly dissipated due to the combination of diurnal drainage winds and developing offshore flow. "Sfc pressure gradients remain offshore with -8.8 mb SAN-TPH and -3.3 mb SAN-DAG," the service reported, noting that these conditions contributed to peak wind gusts, including a notable 54 mph gust at one location. High temperatures in valleys are anticipated to be 10-15 degrees above average.
Looking ahead, the robust offshore winds are expected to wane by Sunday afternoon, allowing a sea breeze to develop. However, this respite is brief, with the presage of another round of weak offshore flow returning by Monday and Tuesday mornings, which could produce gusts of 35-40 mph in certain passes and foothills. The forecast further indicated a possible return of marine layer clouds and fog to the immediate coast on these mornings.
The remainder of the week sees a cooling trend, with temperatures gradually returning to their normal ranges by Thursday, as more persistent onshore flow sets in. "A closed low about 650 miles southwest of San Diego will be drawn into the mean westerly flow aloft, by a shortwave trough moving southeast from the Pac NW and eventually moving across the region sometime Fri-Sat," the National Weather Service predicted. They also highlighted that a significant number of ensemble forecast models suggest the potential for precipitation towards the end of the week, though uncertainties in timing and amounts persist.
