As we navigate the mid-October weather patterns in San Diego, forecasts indicate a seesaw of temperatures, with a cooling trend mid-week followed by a spike in temperatures towards the weekend. According to NWS San Diego, Monday saw highs ranging from the low 70s along the coast up to the low 90s in the low desert.
On Tuesday, locals can expect "similar temperatures to Monday with slightly cooler temperatures for the coastal/western valley regions," as NWS San Diego reports. Despite the brief dip in temperatures, the high pressure sticking around will ensure above-average high temperatures for inland areas through Tuesday. However, as the week progresses, a transition is in the air, with a low-pressure system bringing a remarkable dip. High temperatures on Wednesday for the mountains and deserts will cool as much as 12 to 18 degrees from those on Tuesday.
The Area Forecast Discussion from National Weather Service San Diego expands on these fluctuations. A shallow marine layer returning to the coast will deepen by Tuesday night, leading into Wednesday. This shift will usher in cloudier conditions and a substantial temperature drop "as much as 5 to 10 degrees below average for the mountains and valleys."
As for the latter part of the week, a restoration of warmth is on the horizon. "High pressure moving inland across California will bring warming for Thursday and Friday," the NWS San Diego details, with inland temperatures expected to climb approximately 5 degrees above average by Friday. Yet, the pendulum swings back, come weekend, as a low pressure system moving inland to the north will strengthen the onshore flow cooling temperatures once again, a few to around 5 degrees below average.
The immediate forecast from NWS's detailed 7 Day Forecast for San Diego calls for patchy fog tonight and tomorrow morning, before giving way to a midweek that will cool down to a high near 69 on Wednesday. The latter half of the week sees a steady warm-up, with mostly sunny skies and highs inching back up to the mid-70s by Friday.
