WHEN: Just about any time of the year is good for a trip to San Diego, but don’t expect the water to be warm in winter. It’s best to avoid summer when school’s out and thousands head to Disney California, which is just an hour and half away. September is a great time, when the temps are still warm, and kids are back in school. February, which is when we go most of the time, is pleasant-to-cool. You can do quite a bit at that time, the beaches are mostly empty, but the waters are not the warmest to swim in, but it’s never stopped us from taking a dip. Therefore, mid to late February is a great time for deals and shorter lines, and we have flown for as low as $50 RT from DFW. D & S have been to San Diego between 1.5 and 6 years and…