SAN DIEGO — If you’ve been in the desert or inland the last few days and experienced the warm up in temperatures and then come to the beach and experienced a complete lack of sunshine, there’s a reason for that — and apparently a name for it, too.

“Not only do we have the “May gray” and the “June gloom,” but when it happens a little bit earlier in April, we call it “Gray-pril,” said Elizabeth Adams, meteorologist with the National Weather Service.

None of these descriptions are official meteorological terms but they help describe what’s going on.

“Basically what’s happening is the deserts are heating up and with that lower pressure with the heat in the desert, all of this marine layer air is pushing from the ocean on to the coast. That’s bringing cooler temperatures and higher humidity, which leads to that fog formation,” Adams said.

Our Southern California coast has been noticeably missing the sunshine, covered in fog the last few days.

“This is kind of unusual for this time of year. This usually comes a little bit later, these fog banks,” Reuben Sanchez said.

The National Weather Service issued a dense fog advisory Monday night into Tuesday morning at 9 a.m. The marine layer that’s been hanging out offshore is expected to move inland, leading to fog near the beaches, but also in the western valley areas.

“Typically May and June is when we have the grayer conditions. April is usually a beautiful month. Hoping to get back to that,” Jeff Hoyle said.

A stark contrast to last April when San Diego was experiencing record-breaking heat.

“Seeing that big thick bank of fog and low clouds on the coast and even just off the coast, that could be a little bit shocking to your system because we are expecting kind of those nicer conditions this time of year,” Adams said.

Under this fog advisory, visibility can drop down to less than half a mile creating hazardous driving conditions and possible flight delays.