April 2026
Region 4: San Joaquin & Tulare
Millerton Lake serves as the focal reservoir for Region 4. A snapshot of current storage conditions from the Department of Water Resources is included below. To the right, storage levels for the current water year (dark blue) are shown alongside analog years (2018–19 and 2024–25) for context.
CAP model output indicates that Region 4 will receive 92.5-112.5% of normal precipitation. For Region 4, 92.5-112.5% of normal equates to 21.98-26.73”.
The regional gauge below shows the CAP forecast lower and upper bounds (21.98-26.73”), the “normal” for Region 4, and the observed precipitation through April 6. In March, Region 4 received only 0.03 inches of precipitation, while the start of April has proven far more productive with 0.73 inches in the first few days. From March 1 to April 6, Region 4 has gained a total of 0.76 inches, representing an increase of 3.2 percentage points. This brings Region 4 to 89.4 % of water year normal, and within 3 percentage points of the CAP verification range for Region 4.
PLEASE NOTE: Water-year averages and accumulations are calculated using the California–Nevada River Forecast Center (CNRFC) monthly precipitation observations, which provide station-level precipitation totals across valley floor, foothill, and mountain locations. These observations are sourced directly from the National Weather Service CNRFC precipitation monitoring dataset and are used to derive regional water-year accumulations and percentages of normal for each CAP region.
San Joaquin & Tulare
