Residents of Southern California may be getting a slight reprieve from recent high temperatures as a low-pressure system from the Pacific Northwest brings cooling across the region. According to the National Weather Service San Diego, inland areas like the valleys and inland Orange County are seeing temperatures 5 to 15 degrees cooler than earlier in the week, with coastal areas remaining in the lower 70s. The marine layer will also deepen, potentially bringing coastal low clouds deeper into the valleys by the weekend.
The cooling comes with a caveat, though, as the same weather report indicates gusty southwest to west winds are expected across the mountains and deserts this afternoon and into the evening, with gusts reaching 30 to 40 mph and isolated gusts up to 50 mph. This, combined with relative humidity plummeting to 5 to 10 percent in the deserts and desert slopes, creates critical fire weather conditions. The winds are expected to weaken alongside a slight increase in humidity towards the end of the week, offering some relief for the concerned areas.
Despite cooler temperatures becoming the norm for the week, with highs generally below average, the region still faces ongoing fires. The Bridge, Line, and Airport fires continue to impact visibility and air quality, with the National Weather Service forecasting the smoke to spread east and northeast across the deserts due to the southwest-to-west flow aloft. Satellite imagery has revealed low cloud areas over the San Diego County coastal waters, which may push farther into inland valleys each night in the coming days.
The cooling trend is expected to persist, with yet another low-pressure system slated for early next week promising another 5 to 10-degree drop in temperature. Forecast discussions suggest significant temperature dips for the mountains and inland valleys, taking them to 15 to 20 degrees below average. In the desert areas, afternoon highs might slide into 100 to 106 degrees today but are predicted to fall to the upper 90s to 103 by Thursday.
The marine conditions along the coast appear favorable, with no hazardous marine conditions expected through Sunday. Maritime activities should continue uninterrupted. On the fire weather front, the reduced wind activity towards the end of the week should aid firefighting efforts and lower the risk of new fires starting. However, vigilance remains critical due to ongoing conditions.
