I meant that it was wrong for 1990. It says I'm in zone 8b, but I moved here in 1984 and every source told me I was in zone 9a at that time. It didn't suddenly get colder 6 years later in 1990. If anything, the winters have steadily grown warmer. Furthermore, the 1990 map also looks faulty because not one of the temperature readings below 20 degrees that I mentioned in my previous post took place in 1974-1986, the period on which the 1990 map is based.
