The Kentucky Division of Water continuously monitors hydrologic conditions throughout the state, including precipitation, streamflows, lake elevations and various drought indices.  This information is used to detect emerging drought conditions, to identify the locations and severity of drought and to provide timely and appropriate public notification.

Statewide Summary of Drought Development

Updated June 17, 2009

Conditions across the state are normal at this time.  The Division of Water will continue to monitor the potential development of drought conditions as we move forward. 

Useful Drought Indicators

PRECIPITATION
The Division of Water monitors a network of 24 daily climate-reporting stations to track developing shortages of precipitation.  For the year to date, precipitation totals for Kentucky range from 60 percent of normal in the Western climatic division to 109 percent of normal in the Bluegrass division.  For the same period, precipitation totals in the Central and Eastern climatic divisions are both at 97 percent of normal.  The current 30-day precipitation totals for the Western, Central, Bluegrass and Eastern climatic divisions average 62, 69, 73 and 46 percent of normal, respectively.

STREAMFLOWS
Overall, current streamflows are within a normal range of expected discharge for this time of year.  An expanded look to the 28-day average streamflow indicates that recent flows have been slightly below normal for the Big Sandy, Upper Cumberland, Lower Cumberland, Kentucky and Tennessee river basins along with the Purchase area.  In the Little Sandy, Licking, Kentucky, Upper Cumberland and Tradewater river basins the 28-day average flows are below normal.  Seven-day average streamflows are above normal for the majority of Kentucky.

LAKE ELEVATIONS
Most small water supply lakes have been returned to normal elevation by winter precipitation following last year’s drought.  All lakes under the control of the Huntington District, Louisville District and Nashville District of the U.S. Army Corps of Engineers are currently at or above normal winter pool elevations.    Releases from Corps of Engineers reservoirs are important to the status of many Kentucky rivers as sources of supply for drinking water, assimilation of wastewater discharges, water quality and aquatic habitat.  These rivers include the Green, Barren, Rough, Nolin, Kentucky, Salt, Licking and Big Sandy rivers.

DROUGHT INDICES

Assessing the severity of a drought is made easier with the use of drought indices that combine various source information into a single representative value of drought severity.  The Palmer Drought Severity Index uses data for precipitation, temperature and evapo-transpiration to calculate a number that can be compared across different times and locations.  This index was developed in the 1960s in Kansas and Nebraska but has since become a part of drought monitoring in a majority of the United States.  The Palmer Drought Severity Index is updated weekly on Monday afternoons.

The Drought Monitor represents a comprehensive assessment of several factors that contribute to the development of drought or that indicate the severity and potential persistence of drought.  The Drought Monitor is updated weekly on Thursday mornings.

Updated June 17, 2009 

Palmer Drought Severity Index values issued on Feb. 28, 2009, are near normal for the entire state.  Assigned values for the Western, Central, Bluegrass and Eastern climatic divisions are 0.43, 0.80, -0.08 and 1.04, respectively.

• 0 to -0.99 = near normal
• -1.00 to -1.99 = mild drought
• -2.00 to -2.99 = moderate drought
• -3.00 to -3.99 = severe drought
• -4.00 and below = extreme drought

It is important to note that the Palmer Drought Severity Index is used as a general index of drought over large geographic areas defined by the four climatic divisions of Kentucky.  Rainfall that affects one part of a climatic division may substantially improve drought conditions on a county or multi-county level but have little or no impact on the regional average conditions defined by the Palmer Index.

Updated June 17, 2009

The U.S. Drought Monitor lists no areas of drought designation for the state of Kentucky.

As a drought indicator, the Drought Monitor is not limited to four large climatic divisions, rather it incorporates the Palmer Index as just one of several indicators of drought development in a given area. These other indicators include more short-term components including the Crop Moisture Index, Standardized Precipitation Index and weekly streamflow percentiles.  The Palmer Drought Severity Index and the Drought Monitor should be considered in combination with more localized data such as rainfall, streamflows, groundwater levels and climatic outlooks to form an accurate assessment of drought severity in a given location.

OTHER LINKS OF INTEREST:

• The Federal Emergency Management Agency (FEMA) provides additional water conservation tips to help you conserve water at home.
• Additional sources of weather-related information include the Kentucky Climate Center at the Department of Geography and Geology at Western Kentucky University.
• The Drought Severity Map is available from the Climate Prediction Center of the National Oceanic and Atmospheric Administration and presents drought conditions for the entire United States on one page.
• The Department of Biosystems and Agricultural Engineering of the College of Agriculture at the University of Kentucky also contains Kentucky weather information, including maps indicating amount of rainfall, temperature and moisture index.
• The United States Geological Survey (USGS) maintains a gauging station database that provides streamflow gauging data for the major river basins in Kentucky.