Prior literature has found evidence that pleasant weather (namely, sunshine) leads to higher tipping rates, presumably because it improves the moods of either servers or patrons. However, studies examining the relationship between pleasant weather and tipping behavior have involved relatively small samples of participants and daily observations. In addition, only one such study (Cunningham, 1979) used actual weather data to examine this relationship. We address these shortcomings by testing empirically the weather–tipping relationship on 2 years of actual sales data from a busy restaurant. We found no statistically significant relationship between sunshine and tipping. Tipping appears to be better explained as an institutional standard or norm, rather than as a prosocial behavior that can be modulated by weather-induced changes in mood.