Not too much to add to what
@Trix said, but the significance of the August report is that its prediction for January 1 forms the basis for how much is planned for release in WY2024. The key number there is 3575. And because the prediction is that Powell will be below that level on New Years Day, and because Mead will be under 1075, the protocol is to release 7.48 maf next year. That's the plan. Of course, all that could change if we get a really big runoff in the spring, and they would likely release more, just as they did this year after originally planning to release 7.0 maf (by the end of WY23 the total release will be about 8.8 maf). The plan could also change if the 2007 Interim Guidelines are updated by then, and the protocol would change as a result. Bottom line is way too early to tell what's going to happen next year. But BOR (actually NOAA) is relatively optimistic in their runoff prediction, likely in part because of this year and because of the El Nino ahead.
As Trix said, BOR sees the lake most likely peaking at somewhere about 3599 in July, with a low of 3566 in the spring. That's based on a predicted unregulated inflow of about 10 maf, which is way less than actually happened this year (which will end up around 13.75 maf by the end of WY23), but a bit above the average since 1991. So a repeat of this year would likely drive the lake well above 3600.
August is also the month when they release their Max- and Min- probable scenarios, and I have to say they look way more rosy then their similar guesses last year. Their "max probable" seems like something from the distant past, with an unregulated inflow of over 17 maf, and the lake peaking at over 3657. If that kind of runoff actually happens (and it hasn't since 1986), the BOR will most certainly release a lot more than 7.48 maf, which will likely suppress the peak summer elevation closer to 3630 than 3650. Still, I like the optimism. Even the "min probable" scenario is not that bad--sort of a repeat of 2020 or 2022, unregulated inflow around 6 maf, not good but not catastrophic either. Even in that scenario, they don't see Powell dropping below 3553 in spring, with a most recovery to a little better than 3566. Not good, but still way better than where things stood going into 2023.
But for now, the main takeaway is it's way to early to know anything, but NOAA is more optimistic about snowpack/runoff than they've been in a few years. Powell will not be flirting with anything close to 3525 next year. Most likely it will peak somewhere from 3585-3610 next summer, but the winter ahead will provide the needed clarity... until then, we're just guessing...
