It is well known that rates of transmission of some respiratory viruses, including influenza, tend to fall during the summer months. As COVID-19 has spread across the globe, questions have been raised about whether warming temperatures, humidity and UV index might slow, or even halt, the spread of SARS-CoV-2, the virus that causes COVID-19. These effects on virus transmission will be important to understand as warmer months ease in and states across the country consider and implement reopening plans. Mount Auburn Hospital says that while the rate of COVID-19 incidence does decrease with warmer temperatures up until 52 degrees F, further warmer temperatures do not decrease disease transmission significantly. A higher UV index also assists in slowing the growth rate of new cases, but the overall impact remains modest. Precipitation patterns did not appear to have any effect on virus transmission.