South Texas Weather Modification Association
Current Operational Status:
The 2016 operational season is in its final month of 2016.  There have been 38 seeding
missions so far this year (April: 1, May: 4, June: 7, July: 7, August: 9, September: 8, October:
3).  Check the Operations page for detailed information on the seeding that has taken place.
Welcome to the South Texas Weather Modification Association
(STWMA) Information Page

The South Texas Weather Modification Association is a non-profit organization consisting of
several water districts committed to enhancing rainfall across the south Texas operation area.  
Rainfall enhancement is conducted using cloud seeding techniques where aircraft release
silver iodide and calcium chloride into thunderstorms to increase rainfall efficiency.

The association first formed in 1996 and conducted its first cloud seeding mission the following
year. After nearly 20 years in existence, the STWMA, based in Pleasanton, continues to
perform seeding operations over multiple counties in south-central Texas.

A map of other associated weather modification projects across Texas area can be found

A overview presentation of weather modification in Texas can be found
here. (Provided by the
Texas Weather Modification Association)

Feel free to navigate around the website, whether it's to check our radar image for current
activity, to get the local forecast and conditions for the target area, or read our FAQ page to
learn more about cloud seeding.
Other Weather Modification Programs in Texas:
  • Panhandle Groundwater Conservation District:  PGCD
  • Seeding Operations and Atmospheric Research: SOAR
  • West Texas Weather Modification Association: WTWMA
2016 Project Counties
All Data, Documents, and images on this site are property of the South Texas Weather
Modification Association. Using or duplicating any data, documents, or images is not allowed
unless granted by written permission from the Chairman or webmaster.