May 2026
Precipitation
During May 2026, Indiana’s average precipitation was below normal in northern Indiana and above normal in southern Indiana, with a statewide monthly precipitation average of 103.3 percent normal. The overall monthly temperature average for Indiana was 60.7 degrees Fahrenheit or 1.8 degrees below normal.
Three of the nine climate divisions received below normal to much below normal precipitation for May (see Percent of Normal Precipitation Table). Climate Division 9 (SE) received the highest (142.7) percentage of normal precipitation for the month, while Climate Division 1 (NW) received the lowest (36.1) percentage.
Precipitation for the year to date (2026) ranges from 89.5% to 109.2% through May. Precipitation for the Water Year 2026 to date ranges from 83.7% to 101.0% through May. Over the 2-year period (from June 2024-May 2026) all nine climate divisions have received below normal to near normal precipitation ranging from 82.1% for Climate Division 3 (NE) to 103.6% for Climate Division 8 (SC).
The 12-month and 6-month SPI indices show all climate divisions in the “near normal” category. The 3-month SPI indices show Climate Division 2 (NC) and Climate Division 8 (SC) in the “very wet” category; climate divisions 3 (NE), 4 (WC), 5 (C), 6 (EC), and 9 (SE) in the “moderately wet” category; with the remaining climate divisions in the “near normal” category. The 1-month SPI indices show Climate Division 1 (NW) in the “severely dry” category; Climate Division 2 (NC) in the “moderately dry” category; climate divisions 5 (C), 6 (EC), 8 (SC), and 9 (SE) in the “moderately wet” category; with the remaining 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 June 2, 2026, the U.S. Drought Monitor shows the northwestern and the very southern tip of Perry County are experiencing “Abnormally Dry” conditions. While the rest of the state is not experiencing any drought conditions. The U.S. Seasonal Drought Outlook predicts the current areas in drought to remain in drought conditions through at least the end of August 2026.
Streamflow
In May 2026, ten of the twelve streams included in drought reporting since 1999 had near normal to much above normal stream flow. Eel River at North Manchester had the lowest mean monthly flow at 70%, and the East Fork White River at Seymour had the highest mean monthly flow at 267%.
Lake Michigan
On May 29, 2026, the Lake Michigan-Huron water level was 4 inches above the measurement taken on April 29, 2026, and 7 inches above the measurement taken on May 29, 2025. On May 29, 2026, the Michigan-Huron mean level was 579.27 feet, which is 33 inches above the lowest recorded monthly mean level for May set in 1964. A comparison of May monthly mean water levels to the long-term (1918-present) average shows Lakes Michigan-Huron water levels were about 3 inches above 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 increase by 2-inches over the next month.
Reservoirs
On May 31, 2026, the water levels for all eight reservoirs monitored by the U.S. Army Corps of Engineers were above the normal pool elevation. The deviation from normal pool ranged from +0.63 feet (Salamonie) to +20.0 feet (Cagles Mill).
All three reservoirs monitored by Citizens Water (Morse, Geist, and Eagle Creek) were above their respective normal pool elevations as of June 1, 2026. The deviation from normal pool ranged from +0.33 feet (Morse) to +0.72 feet (Eagle Creek).
Groundwater Levels
As of May 31, 2026, new water level data is available for all nine wells currently monitored. Data indicates that water levels remain below to well below normal for six of the nine wells: Laporte 9, Fulton 7, Vigo 7, Morgan 4, Randolph 3, and Posey 3. Data indicates that the water level is near normal for LaGrange 2 and Harrison 8 and well above normal for Clark 20.
Real-time data is available for all of the wells and may be accessed on the U.S. Geological Survey 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
