Thousands of NYSEG electric customers across New York State should be prepared for higher bills in April.

The utility is warning customers that the bill for a "typical residential electricity customer" in April may be about 15 to 20 percent higher than last month's bill.

Bob Joseph/WNBF News

NYSEG says it is reconciling electricity supply prices to account for differences between the predicted prices and the actual market-based prices from January.

The company says cold temperatures combined with higher electricity supply prices already resulted in increased costs for customers.

NYSEG says the utility forecasts electricity supply prices and then bills customers based on its predictions.

The company says because the actual electricity costs for January were higher than predicted, the increased expense to customers will be spread over April and May.