Introducing ALICE
What began as a California-specific capability has now been extended well beyond the state. Over the past year, we’ve evaluated the technology behind CAP to determine whether the same seasonal precipitation signal appears in other regions and climate regimes.
Across multiple continents and climate regimes, the same underlying signal is present—consistent, measurable, and predictive.
These results demonstrated the need for a broader forecasting framework. We refer to this technology as ALICE (Atmospheric Linkages Informing Community Expectations). CAP is the California implementation of ALICE.
View the initial 2025–2026 water year forecast.
Core Supply Dashboard
WY 2025–26 Precipitation Forecast: Near Normal Overall, Slightly Wetter in the North
Following an “average” year in 2024–25, precipitation for water year 2025–26 is projected to be near normal across California. Forecast guidance suggests a modest north–south gradient, with conditions trending near to slightly above average in the northern portion of the Core Supply region and near to slightly-below average in the south.
See the Regional Sections for a more detailed breakdown by region.
The dashboard below shows the Core Supply status (Regions 2, 4, and 6, shaded blue) with observed data through April 6, 2026.
Core Supply:
CAP Forecast WY 2025-26
Highlights
- March was dry. The Core Supply received a mere 0.09 inches of accumulation. The first few days of April were far wetter, with an accumulation of 1.14 inches. Together this resulted in a gain of 1.23 inches, increasing water year progress by approximately 4 percentage points.
- With a total water year accumulation of 25.31 inches, the Core Supply sits at 92.3% of water-year average, just 2.7 percentage points shy of the CAP forecast range.
- Because of the modest precipitation in March and early April, the current water year accumulation traces are now slightly below those of analog years 2018-19 and 2024-25. See the Insights Section for accompanying graphics and a comprehensive discussion of precipitation through March and into April.
- Please note, observed reservoir inflows through April 6, 2026, are available in the CRAFT section of the portal.
Latest Insight
Monthly Update: Dry March, but on Track
California Water Watch (CWW) precipitation maps, with CAP regions overlaid, illustrate water-year-to-date totals as a percent of average through last month’s update on March 9 (top) and through April 4 (bottom), with statewide statistics included alongside each map.
On March 9, statewide water year-to-date precipitation stood at 18.8 inches (108% of average). By April 4, totals had increased to 19.35 inches, but the percent of average dropped to 97%, as typical seasonal accumulation outpaced the observed precipitation.
CAP: Regional Reports
Sacramento, Yuba, Feather & American
Russian, Napa, & San Francisco Bay
San Joaquin & Tulare
Kern & Kings
CRAFT | Reservoir Inflow Forecast
Water Year 2025-26 With Observed Data through 4/6/2026
Trinity Lake
Lake Shasta
Lake Oroville
New Bullards Bar Reservoir
Englebright Reservoir
Folsom Lake
Pardee Reservoir
New Hogan Reservoir
New Melones Reservoir
Hetch Hetchy Reservoir
New Don Pedro Reservoir
Exchequer Reservoir
Millerton Lake
Pine Flat Reservoir
Lake Kaweah
Lake Success
Lake Isabella
