As we reported last month, the continental United States is forecast to experience numerous regionally significant water anomalies:
- Exceptional drought will persist in northern California through the Pacific Northwest;
- Southern California is forecast to have characteristics of both water deficits and surpluses;
- Exceptional water surpluses are forecast for portions of Texas, Oklahoma, Kansas, Nebraska, Colorado, New Mexico, and Louisiana.
In addition, the current forecast indicates:
- a wide belt of moderate to exceptional surpluses is expected from the Central Plains eastward;
- Southeast states are forecast to have characteristics of both water deficits and surpluses.
WSIM Composite Water Anomaly Index for April 2015 through March 2016
(12-Month)
The 3-month composites (below) for the same 12-month period show the evolving conditions in more detail. (It should be noted that forecast skill declines with longer lead times.)
- Deficits on the West Coast may spread through September, moderate October through December, and then transition to surpluses in California December through March;
- The region of exceptional surpluses in the Southern and Central Plains is forecast to expand into the US Southwest and northwest Mexico July through March;
- The October through December forecast includes 10-20 year water surpluses along the Mississippi River;
- A broad band of surpluses may emerge in the Central Plains July through September and expand from October through March to encompass much of the country;
- Surpluses are forecast to emerge in the Southeast January through March with exceptional surpluses forecast for southern Florida.
WSIM Composite Water Anomaly Index for April 2015 through March 2016
(3-Month)
- November 2024 8
- October 2024 13
- September 2024 13
- August 2024 13
- July 2024 13
- June 2024 13
- May 2024 13
- April 2024 14
- March 2024 13
- February 2024 13
- January 2024 13
- December 2023 15
- November 2023 12
- October 2023 18
- September 2023 13
- August 2023 13
- July 2023 11
- June 2023 15
- May 2023 14
- April 2023 17
- March 2023 15
- February 2023 9
- January 2023 14
- December 2022 14
- November 2022 14
- October 2022 14
- September 2022 14
- August 2022 14
- July 2022 14
- June 2022 14
- May 2022 14
- April 2022 14
- March 2022 14
- February 2022 14
- January 2022 14
- December 2021 14
- November 2021 14
- October 2021 14
- September 2021 15
- August 2021 14
- July 2021 14
- June 2021 14
- May 2021 14
- April 2021 14
- March 2021 14
- February 2021 14
- January 2021 14
- December 2020 14
- November 2020 14
- October 2020 14
- September 2020 14
- August 2020 14
- July 2020 14
- June 2020 14
- May 2020 14
- April 2020 14
- March 2020 14
- February 2020 14
- January 2020 14
- December 2019 1
- November 2019 14
- October 2019 14
- September 2019 14
- August 2019 14
- July 2019 14
- June 2019 14
- May 2019 16
- April 2019 14
- March 2019 17
- February 2019 25
- January 2019 2
- December 2018 14
- November 2018 14
- October 2018 14
- September 2018 14
- August 2018 14
- July 2018 14
- June 2018 14
- May 2018 14
- April 2018 14
- March 2018 14
- February 2018 14
- January 2018 15
- December 2017 21
- November 2017 8
- October 2017 15
- September 2017 14
- August 2017 14
- July 2017 14
- June 2017 14
- May 2017 14
- April 2017 14
- March 2017 15
- February 2017 15
- January 2017 14
- December 2016 18
- November 2016 10
- October 2016 14
- September 2016 14
- August 2016 15
- July 2016 14
- June 2016 14
- May 2016 15
- April 2016 14
- March 2016 15
- February 2016 14
- January 2016 14
- December 2015 14
- November 2015 14
- October 2015 12
- September 2015 11
- August 2015 11
- July 2015 16
- June 2015 6
- May 2015 9
- April 2015 10
- March 2015 6