Weather Normalization Adjustment for Residential Customers

A WNA is a factor that helps level out high gas bills due to colder-than-normal weather and low gas bills due to warmer-than-normal weather. 

For the 2024 – 2025 winter heating season normal degree-days will be based on the period from October 1994 through May 2024. No WNA adjustment occurs if these normal weather conditions occur. Weather conditions colder than normal will result in a credit. Weather conditions warmer than normal will result in a surcharge. The WNA factor, based on customer usage and weather conditions during each billing period, will be used to calculate the amount of the credit or surcharge.

WNA benefits customers in the following ways:

1. Customers will receive a credit on their bills during colder-than-normal weather when bills are typically at their highest. 
2. WNA provides Virginia Natural Gas (VNG) revenue stability, enabling the company to better plan and schedule system maintenance and improvements contributing to operational quality and pipeline safety.

Yes, many states have approved a weather normalization adjustment for natural gas companies. WNA has a proven track record of working well for both customers and gas companies in many states throughout the country. The use of weather adjustments began in the early 1980s and has grown substantially to include many gas companies across the country and in Virginia. 

No. The WNA is designed to be revenue neutral because it reduces bills when the weather is colder-than-normal and surcharges bills when the weather is warmer-than-normal. The calculations used to determine these amounts are based on the method and data approved by the VSCC.

All residential customers will see a WNA on their bills during the heating season.

WNA is effective for six billing periods during the heating season beginning with billing cycle 10 in November. Billing cycles 10-21 will have a WNA on their bills November through April and billing cycles 1-9 will have a WNA on their bills December through May.

For example, when the weather is five percent colder or warmer than normal a typical residential customer will receive a WNA credit or surcharge of approximately $23 spread over six bills.

A WNA factor adjusts your delivery charge during the winter months for fluctuations in normal weather. The factor is based on customer's weather sensitive portion of their bill, defined during the 2024 – 2025 heating season as usage greater than 8.8 ccf (hundred cubic feet). CCF of natural gas used and weather conditions (heating degree-days) during each bill period, are used to calculate the amount of your WNA bill credit or surcharge. The actual heating degree-days in the bill period are compared to the normal heating degree-days for the period to determine if the weather is colder or warmer than normal. Normal weather for the 2024 – 2025 heating season is an average of temperatures in our service area over a 30-year period from October 1994 through May 2024. Heating degree-days are calculated by subtracting the average temperature for the day from 65 degrees F. Sixty-five degrees is considered the base temperature at which most homes and buildings would be comfortable. Heating degree-days statistics provided by the National Oceanic and Atmospheric Administration (NOAA), a government agency that tracks weather conditions, are used to calculate the WNA factor.