An interesting report, but is there any reason to conclude that "we are due"?

If the lack of rain is random (like flipping a fair coin), the expected time to event would still be 1000 years. Believing that "heads" is more likely after a string of "tails" is the classic Gambler's Fallacy: https://en.wikipedia.org/wiki/Gambler%27s_fallacy

If on the other hand the current drought is caused by a change in climate, there is even less reason to believe that we are due for a gigantic amount of rain. If the coin is biased (bent) logic would conclude that one should bet that recent performance _is_ an indicator of future performance.

While it's not impossible for alternation to be most likely, it requires some physical process that would explain it. Interestingly, weather in the Central California often does follow multi-week cycles, with hot inland weather leading to rising air at the coast, leading to fog flowing inland, leading to a cooldown[1]. But I don't know of any process that would explain this for century scale rainfall. Do you?

[1] This article offers an explanation of the "fog cycle", but with the cautious wording "Until recent years, the conventional explanation for the fog’s behavior was a simple one". I wonder if there is now better knowledge: https://baynature.org/articles/cutting-through-the-fog/