Sacramento starts a new water year after a split season: wetter North, very dry South. A weak La Niña may form this fall, then fade to neutral in winter. The 2024–25 water year closed with Sacramento near 13.81", below normal, while Northern basins ranked wetter and Southern California and deserts were among the driest. Looking ahead, guidance favors a weak La Niña peaking before year-end, then neutral through the core wet months. Seasonal models lean warmer/drier for the West, but confidence is limited. Sub-seasonal shifts like the PNA and a North Pacific warm-water “blob” could alter storm tracks. Climatology: Sacramento’s first 0.25" day typically late October; most ≥1" days arrive mid-December.
Sacramento’s water year recap and a weak La Niña ahead

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