SAN DIEGO — If you’ve noticed an increase in low hanging clouds or lingering fog in San Diego County’s coastal areas recently, there’s a reason why.
The National Weather Service says the region is in the peak of marine layer season. The question is: what creates these hazy weather patterns in the spring?
The answer is as simple as this — cold water.
Air temperature normally decreases with height, according to weather officials. Due to the cold Pacific Ocean in the spring months, however, NWS says the air temperature in coastal areas increases with height instead.
NWS says this results in a temperature inversion. The air below that inversion is called the marine layer, which is cooled to the point at which clouds form, weather officials explained. NWS shared this image to explain the marine layer.

To explain this phenomenon further — As the San Diego region progresses towards summer months, the ocean temperature gradually rises which then causes the coastal temperature to rise, said NWS. As the inversion becomes weaker, the low clouds and fog aren’t as widespread come July and August, according to weather officials.
More information on the marine layer can be found here.
Looking ahead, NWS says “a major cool down” can be expected Monday after a warm weekend and thick marine layer clouds may spread inland. Weather officials say patchy marine layer drizzle is also possible as early as Tuesday.
Hang in there San Diegans — the dreariness won’t last forever.