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Each growing season, producers try to balance expected rangeland forage production and expected animal intake needs to sustain animals and achieve expected animal gains.  Drought conditions make this stocking decision more difficult.   Available soil water from precipitation is the main limiting factor to total forage production in most regions. Other factors such as prior grazing history (stocking rate) and time of year in which grazing took place also can affect forage production in future growing seasons. To plan for future drought periods, it would be beneficial to know the amount of pasture production that could be expected from decreasing amounts of precipitation so that producers can make informed stocking decisions.  Rangeland production was compared with annual precipitation or specific monthly combinations of precipitation data for 35 years to find the best relationships between the times of year precipitation is received and end of the growing season forage production.  Animal gain data was then correlated to seasonal precipitation periods to analyze precipitation effects on steer gain.  The time period of precipitation with the greatest relationship to end of growing season forage production was precipitation from October of the previous year (OctPY) through September of the current year (r2 = 0.61). But, the two-month period that had the greatest relationship with end-of-season forage production was May and June precipitation (r2 = 0.56).  Furthermore, as water year precipitation increased, individual animal daily gains decreased over the same time period.  Refinements in initial stocking may be made during the season based on May and June precipitation, and, as long as animals have adequate forage available to meet daily dry matter intake needs during dry years, animal gains should be able to meet expectations.