I also live in San Diego. My daily commute is 35 miles each way. I drain the battery in the morning and use gas for the last mile or so.We are having the same issue and we live in Sunny San Diego. It's not cold....it's always mid 70's. Still....whenever I charge the clarity it says 37 miles. I was really counting on those extra 10 miles to get me to work and back.
I recharge at work and have 8-10 miles left when I get home. It doesn't seem like it, but the elevation accounts for this difference.
The traffic is the same each way and I haven't been using heat nor a.c.. At home I charge with 120v and charge with 240v at work, but that shouldn't matter.