April 2015—New Weather Attributes and Fahrenheit Temps Available

New Weather Attributes

We've added a few new properties to the current Weather API.

Property Description
Like the accumulated precipitation attribute currently available, these properties provide the accumulated precipitation over the same days from the prior year, an average of the prior three years, and an average of up to 10 prior years (or as much history as we have available).
Similarly, these properties provide the accumulated GDD over the same time period from the prior year, an average of the prior three years, and an average of up to 10 prior years.
Potential Evapotranspiration (PET) is the amount of water likely to disappear from the ground as a result of temperature, wind, relative humidity, and other variables. These attributes are being added to aid in providing decision support around irrigation and/or crop stress. pet will be the given day's calcualted PET value (expressed in millimeters), and accPet will be the accumulated PET from the start date to each date in the range (or from the plant date, where supplied).
ppet Precipitation over PET (P/PET) is the ration of precipitation received over the potential evapotranspiration of the area. A value over 1 implied more moisture was received than what disappeared, while a value under 1 implies increased aridity and potential water stress.

Fahrenheit Now Available

By default the API returns temperature units in Celsius and GDDs are calculated using Celsius figures. For customers in the US this can create an additional hassle of having to convert to Fahrenheit for display in your applications to US farmers. We've added a new optional query string parameter called temperatureUnits that when set to fahrenheit will return temperature values in Fahrenheit and GDDs will be calculated using the Fahrenheit values. (The resulting GDDs will be 1.8X larger than the Celsius-calculated values.)

Example call using Fahrenheit: