The number of loans past due between 30 and 59 days increased to 2.4% in September from 2% in August and 2.1% in September 2016, according to CoreLogic's Loan Performance Insights Report.

The share of mortgages that transitioned from current to 30 days past due was 1.3% in September, up from 0.9% one year prior.

"September's early-stage delinquency transition rate rose to 2.6% in Texas and it rose to 3.2% in Florida, which is higher than the 1% that's typical for both states," said Frank Nothaft, CoreLogic's chief economist, in a press release. "Texas and Florida's early-stage delinquency transition rates in September are much lower than New Orleans in September 2005 when the transition rate reached 17.4% as a result of Hurricane Katrina."

Mortgage delinquencies increased in September

Mortgage Guaranty Insurance Corp. is the only mortgage insurer that puts out monthly data on changes to its inventory of delinquent loans. In November, it received 8,875 new delinquency notices from servicers, of which 4,525 were for loans in hurricane-impacted areas. For November 2016, only 623 new notices were for mortgages secured by properties in hurricane impacted areas.

September's total delinquency rate was 5%, up from August's 4.6%, but down from 5.2% one year prior.

Florida's total delinquency rate of 7.5% was up from 5.3% in August and 6.2% in September 2016.

The delinquency rate in Texas jumped to 6.8% from 5.4% in August and 5.5% in September 2016.

For the fourth consecutive month, the percentage of loans seriously delinquent, those that are 90 days or more late, remained at 1.9%.

The share of mortgages at some stage of the foreclosure process was 0.6%, the same as in August and down from 0.8% in September 2016.

"While natural hazard risk was elevated in 2017, the economic fundamentals that drive mortgage credit performance are the best in two decades," said Frank Martell, CoreLogic's president and CEO. "The combination of strong job growth, low unemployment rates, steady economic performance and prudent underwriting has led to continued improvement in mortgage performance heading into next year."