May 17--Rising natural gas costs will push monthly bills higher for UGI Penn Natural Gas customers next month and again in December, the utility company said Wednesday.

The combined increases will add $19.75 a month to a typical residential customer's bill based on usage figures provided by the utility. The cost increases to be submitted to the Pennsylvania Public Utility Commission on June 1 reflect a quarterly adjustment in the amount the utility pays for gas and an annual rate it expects to pay as of Dec. 1. The PUC routinely approves the quarterly adjustment but reviews annual rate filings before they go into effect. The purchased gas cost accounts for more than half of the monthly bill. The June 1 quarterly adjustment will raise monthly bills approximately 9.9 percent for a residential customer who uses 100 hundred cubic feet a month.

The customer's bill will increase to $145.05 from $131.92 a month. If the PUC approves the Dec. 1 incr ase of 4.6 percent, the customer's monthly bill will increase to $151.67. The June adjustment will be the first purchased gas cost increase for the utility since December 2005, when it was formerly PG Energy. At that time the cost was $1.21 per hundred cubic feet of gas. The cost dropped steadily to $.906 per hundred cubic fe t in December of last year and has held there. The utility said it will raise the purchased gas cost to $1.03 per hundred cubic feet next month and, pending PUC approval, to $1.10 on Dec.

1. Since it last lowered the cost in December 2006, the utility has had to deal with "colder than normal temperatures" in late winter and early spring of this year, factors that have contributed to the higher purchased gas cost, said Bruce M. Davis, vice p esident of gas supply and marketing with the utility. In a prepared statement, Davis said, "our current projections for the next heating season result in higher natural gas prices." Pushing the price up are national weather forecasts for a hot summer, an active hurricane season and "continued globally high energy prices," he said. Should the projections change, the utility can adjust the rate on either a quarterly or interim basis in reaction to market conditions.

The rates apply to all utility customers -- residential, commercial and industrial. Commercial customers who typically use 438 hundred cubic feet a month will pay $579.53 a month on June 1, up from the current rate of $522.04. The December increase will raise the monthly bill to $608.52. Likewise, an industrial customer using 3,160 hundred cubic feet a month will pay $3,846.13 next month instead of $3,431.40 under the current rate. The customer's monthly bill will rise again in December to $4,055.31 a month. Wilkes-Barre based UGI Penn Natural Gas has approximately 158,000 customers in its 13-county service area in northeastern and central Pennsylvania.

It is a wholly owned subsidiary of UGI Utilities Inc. BY THE NUMBERS 19.75 Added cost of two price increases to a typical residential customer's bill. 9.9 percent Approximate amount of price increase by June 1. 4.6 percent Approximate amount of Dec. 1 price increase if approved by the PUC. Jerry Lynott, a Times Leader staff writer, can be reached at 829-7237.