Markets

The utility responded that it is not eligible to declare bankruptcy.

"Investors were not disappointed," said John Kerschner, global head of securitized products and portfolio manager at Janus Henderson. "Inflation came in softer than expected, leading to a tepid bond market rally" and ensuring a rate cut at the upcoming Federal Open Market Committee meeting.

The northern California school district has been struggling for years and on several occasions abandoned plans to consolidate schools, which rating agencies say might have shored up finances.

Jamie Doffermyre  has worked in munis at Truist Securities, Citi and Merrill Lynch.

The upgrade is driven by realized and expected improvement in the state's financial metrics, the rating agency said.

"We're not going to be having huge reinvestment months over the next few months, not until the beginning of the year. So we need this flow [of deals] to keep up with demand, and we expect that to continue," said Jennifer Johnston, director of municipal bonds research at Franklin Templeton.

With the advance refunding of tax-exempt munis still off the table, issuers are using existing market conditions to shed Build America Bonds and realize debt service savings through tender offers.

North Carolina's triple-A ratings were affirmed ahead of plans to sell up to $506 million in general obligation and limited obligation bonds.

The tax-exempt market is expected to be "biased higher" in the coming weeks and months as the expected heavy pace of issuance this month will not be as "oppressive" as feared, said Pat Luby, head of municipal strategy at CreditSights.