Here's more info re: Sea of Cortez
We chartered there in July, hottest month of the year but we were never uncomfortable, lived in bathing suits all day and then it really cools down at night. Winds are 5-15, water is flat, crystal clear, deep, no reefs or shoals. My kids swam and snorkeled with seals. Whales played with us by diving under our boat and then re-surfacing on the other side. The Moorings base is at La Paz, about 50 miles north of the southern-most point of the Baja at Cabo San Lucas. We flew into LAX and then connected on a 1.5 hour flight into La Paz. There are no restaurants or facilities out on the water, only at the marinas, so plan to eat aboard all the time. We left the dock fully provisioned from a local supermarket and could not re-provision all week, but the boat had a great refrigeration system and we were well stocked with food, drinks and ice, fresh water tanks, fuel tank. The local fishermen will trade their catch for beer or whatever. Beware of the "cormwells," 35-40 knot blasts of wind that come through after midnight and are gone by sunrise. Has something to do with the cool Pacific Ocean breezes coming in to fill the voids left by the superheated air. This only affects the southern-most area of the Baja peninsula, from Cabo San Lucas to just north of La Paz. North of there, it doesn't exist. We never dragged at anchor even one inch but it's a little scary until you get used to it. They will tell you about it at chart briefing. Also warned us about rays, but we never saw any at the shores, just swish your feet back and forth as you walk along the water's edge, also told us not to reach into rocky crevices at night (duh!) because of snakes and scorpions but we never saw any. It's kind of like sailing on the moon, all this mountainous reddish/rocky/sandy desert environment leading down to gorgeous beaches. Very few charterers or other boats. Forget your cell phone (maybe satellite phone would work). Bring your portable GPS. The Moorings is a first class operation. It's a once-in-a-lifetime experience sailing the Baja. Let me know if this helps. I'll try to find my chartbook and let you know the publisher and title. Also, check out the Moorings web page. Also, check the archives on this site during the last few weeks, there were some other Baja posts with referrals to some web sites. Let me know what you decide to do or if I can answer any more questions.