A weak upper trough is sliding through Southern California and weak upper ridging will settle in for the rest of the week, leading to warm and mostly dry conditions in San Diego County, according to the National Weather Service.
High temperatures Thursday could reach 70 to 75 near the coast, 80 to 84 inland, 83 to 88 in the western valleys, 89 to 94 near the foothills, 85 to 94 in the mountains and 103 to 107 in the desert.
A new Pacific system is expected to track across the Great Basin this weekend into early next week, gradually cooling temperatures in the county, NWS said.
Looking ahead, another Pacific system could arrive late next week, potentially bringing temperatures back to normal or slightly below.
The marine layer will persist throughout the week with slight fluctuations in its depth and coverage.
