December 2025
Precipitation
December 2025 Indiana’s average precipitation was below normal, with the average temperature also below normal. The statewide monthly precipitation average was 65.0 percent of normal. The overall monthly temperature average for Indiana was 30.3 degrees Fahrenheit or 2.2 degrees below normal.
All nine of the climate divisions received much below normal or below normal precipitation for December (see Percent of Normal Precipitation Table). Climate Division 2 (NC) received the highest (93.9) percentage of normal precipitation for the month, while Climate Division 9 (SE) received the lowest (50.9) percentage.
Precipitation for the year to date (2025) ranges from 80.1% to 115.5% normal through December. Precipitation for the Water Year 2026, beginning October 1, 2025, ranges from 57.9% to 93.3% through December. Over the 2-year period (from January 2024-December 2025), all the nine climate divisions have received near normal precipitation ranging from 86.4% for Climate Division 4 (WC) to 111.1% for Climate Division 8 (SC).
The 12-month SPI indices show Climate Division 8 (SC) in the “very wet” category, Climate Division 3 (NE) in the “moderately dry” category, and the remaining climate divisions in the “near normal” category. The 6-month SPI indices show climate divisions 4 (WC) and 6
(EC) in the “moderately dry” category, Climate Division 3 (NE) in the “severely dry” category, and the remaining climate divisions in the “near normal” category. The 3-month SPI indices show climate divisions 3 (NE) and 4 (WC) in the “moderately dry” category and the remaining climate divisions in the “near normal” category. The 1-month SPI indices show all climate divisions in the “near normal” category.
- Table of recent precipitation compared to normal for each climatic division of the state.
- Standardized Precipitation Index (SPI) drought maps for the state for current month.
- Explanation of Standardized Precipitation Index (SPI)
U. S. Drought Monitor
For December 30, 2025, the U.S. Drought Monitor shows parts of northeast Indiana are experiencing “severe drought” to “extreme drought” conditions. Most of the remaining northern half of the state is experiencing either “abnormally dry” or “moderate drought” conditions. Most of the southern half and northwest counties are indicating no drought conditions, except for an area of “abnormally dry” conditions. The U.S. Seasonal Drought Outlook predicts the current drought conditions to end or improve for the whole state by the end of March 2026.
- State Map
- Latest U.S. Drought Monitor Map for the United States
- Learn more about the U.S. Drought Monitor
Streamflow
In December 2025, all of the twelve streams included in drought reporting since 1999 had below normal to much below stream flow. St. Marys River at Decatur had the lowest mean monthly flow at 6%, and the Kankakee River at Shelby had the highest mean monthly flow at 85%.
Detailed Information on Streamflow
Lake Michigan
On December 26, 2025, the Lake Michigan-Huron water level was 3 inches below the measurement taken on November 26, 2025, and 8 inches below the measurement taken on December 26, 2024. On December 31, 2025, the Michigan-Huron level was 577.49 feet, which is 16 inches above the lowest recorded monthly mean level for December set in 2012. A comparison of December monthly mean water levels to the long-term (1918-present) average shows Lakes Michigan-Huron water levels were about 13 inches below the average. All Lake Michigan-Huron data are referenced to the International Great Lakes Datum 1985.
The Lake Michigan-Huron water level is forecast by the U.S. Army Corps of Engineers to decrease 1 inch over the next month.
Reservoirs
On December 31, 2025, the water levels for six of the eight reservoirs monitored by the U.S. Army Corps of Engineers were above the normal pool elevation. The deviation from normal pool ranged from +0.75 feet (Roush) to -0.8 feet (Patoka).
Two of the three reservoirs monitored by Citizens Water (Morse and Geist) were above their respective normal pool elevations as of December 31, 2025. The deviation from normal pool ranged from -1.37 feet (Eagle Creek) to +0.16 (Geist).
Groundwater Levels
As of December 31, 2025, new water level data is available for all nine wells currently monitored. Of the nine wells, data indicates that water levels are below to well below normal
for Laporte 9, Vigo 7, Morgan 4, Posey 3, Randolph 3, and Clark 20. Extremely low conditions are indicated at Fulton 7 and LaGrange 2. Harrison 8 is near normal.
Real-time data is available for all of the wells and may be accessed on the U.S. Geological website.
Acknowledgments
This report has been compiled from Division of Water data and from information supplied by the following:
Precipitation data:
National Oceanic and Atmospheric Administration, National Weather Service, Midwestern Regional Climate Center
Standardized Precipitation Index (SPI):
National Drought Mitigation Center (NDMC) and Western Regional Climate Center (WRCC)
Streamflow:
U.S. Geological Survey and State of Indiana cooperative program
Lake Michigan level data:
U.S. Army Corps of Engineers, Detroit District
Reservoir data:
U.S. Army Corps of Engineers, Louisville District
Groundwater level data:
U.S. Geological Survey and State of Indiana cooperative program
Temperature data:
Midwestern Regional Climate Center and Indiana State Climate Office, Purdue University