Just wondering how either WD or the Davis VP2 calculated dew point? Mine is reporting about 2 degrees lower in WD than any other station near to me…The temperature and humidity are pretty much the same as others?


It’s a very standard formula. There are many online calculators so plug your temp and hum into any of them to double check your/others results. Here’s one

Or even doing your own calculation using this modified (simplified) formula:

Td = T - ( ( 100 - RH ) / 5 )


  • Td is dew point temperature (in degrees Celsius)
  • T is observed temperature (in degrees Celsius)
  • RH is relative humidity (in percent)

This formula is fairly accurate for relative humidity values above 50%…