The day was planned to be a stunning display of a county whose fortunes are taking flight. Representatives of New York's most prestigious bond rating companies would tour Prince William by helicopter, while county officials regaled the visitors with reports of the county's climb toward becoming one of the economic dynamos of Northern Virginia.

The weather, however, had different plans altogether. When officials of Standard & Poor's and Moody's Investors Service arrived in Prince William Friday, the region was in the midst of a snowstorm.

Instead of a dazzling airborne tour, the financial wizards spent most of their time listening to county officials present a more prosaic description of the county's fiscal condition -- an exercise that would bring even Prince William's most enthusiastic boosters down to earth.

Standard & Poor's and Moody's were in Prince William to make ratings that will be used by investors to determine whether the bonds the county will issue this month are a prudent risk. After voter approval last fall, the county plans to sell $44.89 million in bonds to pay for the construction of new schools.

Investors and the business community at large view the bond ratings as crucial indicators of a locality's fiscal health. The results of Standard & Poors and Moody's studies, which the firms conduct independently, are expected next week, according to county officials.

Right now the county has a rating of AA from Moody's and AA minus from Standard & Poor's, according to Ron Tucker, a fiscal planner for the county government. Although these ratings are acceptable, Tucker said, they aren't as good as the AAA rating given to localities such as Fairfax County and a small number of others around the nation where a large tax base and sound planning have earned a top ranking from the rating firms.

Prince William officials, citing the county's recent progress in buttressing the tax base by luring businesses, said they believe the county's bond rating should be raised -- if not to the AAA rating, at least to the middle step of AA plus.

"We feel there's been tremendous maturity" in Prince William's financial management and tax base, said county board Chairwoman Kathleen K. Seefeldt, who participated in briefings for the bond raters.

On the other hand, county officials acknowledge, the financial challenges facing the county remain formidable. Residential growth continues at a staggering pace, straining the tax base as new residents impose ever higher demands on the public schools and other county services.

The chief incentive for a higher rating is monetary: The higher a locality's rating, the lower rate of interest it must promise investors to induce them to purchase its bonds.

Moreover, county officials said that a high bond rating can be potent symbols when trying to attract businesses to locate in Prince William -- a way of communicating in shorthand that a locality's finances are sound and its future bright.

"They tell anyone who's interested a lot about the county," Seefeldt said.