High Temperature and High Humidity Reduce the Transmission of Covid-19
But not by enough.  This epidemic has a growth rate (R) of at least 2. The article claims "One degree Celsius increase in temperature and one percent increase in relative humidity lower R by 0.0383 and 0.0224, respectively."
The March to July difference for New York City is only 19C. San Francisco, 9C. For both cities, humidity is relatively uniform year round.Even assuming this result is meaningful, it still leaves an R way above 1.