Experts say the major temperature difference actually makes San Diego County unique compared to the rest of the country.

Only along the coast will you find weather cool enough to exercise outdoors. Between 1 p.m. and 2 p.m. Thursday afternoon, it was 71 degrees at Mission Beach.

"It feels like paradise all the time," said Joe Celano, visiting from Atlanta.

However, about 20 miles east into the inland valleys to a city like El Cajon and there is a major difference in temperature and opinion.

"Muggy, hot, sweaty," said Ramona resident June Saunders.

On Thursday, it was 97 degrees in El Cajon, very similar to Ramona.

Unlike the coast, no one really is out and about unless you're walking from your air-conditioned car to an air-conditioned building.

For many, lunch outdoors is not an option.

"I really wouldn't have [eaten] outside. That's why I try to keep it inside and cool," said one East County resident.

Drive farther east and the mercury keeps rising. Over the mountains and down into Borrego Springs, the low desserts, temperatures in the 100s are the norm. Early Thursday afternoon, it was 114 degrees.

"We go out in the morning or late at night," said resident Wendy Quinn.

From the desert all the way out to the coast, the difference in temperatures this day is 43 degrees -- a change in temperature just under a two-hour drive.

The National Weather Service says San Diego County offers the widest range of temperatures and probably the most diverse daily weather in the country rivaling other coastal counties in California.