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Weather Normalization Adjustment (WNA) is a mechanism that adjusts a customer's bill due to variations from normal weather (temperature). For bill periods that are warmer than normal, a surcharge is applied to the bill. For bill periods that are colder than normal, a credit will be applied to the bill. WNA is effective for usage during the months of October through May for customers with gas heat. 

Note 1: WNA factors (expressed in $ per therm) represent 'Service Class' averages. The factor for each customer's account may vary in accordance with the allocation of their base (non-heat) usage and heating (temperature sensitive) usage for billing periods that span a rate change.

Note 2: Usage ranges below are based on a 30 day billing period.

Note 3: See further explanation of the 'Weather Normalization Adjustment' and an example of the calculation.

Note 4: Access the Public Service Commission (PSC) website for the most current 'Weather Normalization Adjustment' (WNC) statement.

Note 5: For bills that are for non-standard periods (e.g. bill dates not listed below) contact Customer Service for additional information.

Applicable to Firm Sales and Transportation customers in the following Service Classifications:

     SC1B      Residential Space Heating
     SC1BR   Residential Reduced Rate Heating
     SC1DG   Residential Distributed Generation
     SC2B      Non-Residential Heating
     SC3B      Multi-Dwelling Heating
     SC16       Year-Round Space Conditioning