A wind advisory issued by the National Weather Service for Thursday has expired but the storm causedmore than 19,000 PSEG customers to lose power since midnight Thursday.

By Thursday evening, however, a spokeswoman for the utility said it had reduced that number to less than 1,000.

In Hempstead, about 5,700 customers lost power on Thursday evening, but PSEG had restored all but about 600 of them within 15 minutes, she added.

The storm produced sustained winds of 20 to 30 mph and gusts up to 50 mph or more, according to the service. The advisory expired at 6 p.m.

According to NWS reports, maximum wind gusts on Long Island were 58 mph in Syosset at 3 a.m. Thursday and in Suffolk, 61 mph at 9:41 a.m. in Orient.

The winds were causing delays of more than an hour at area airports.

“Strong winds — scattered power outages . . . and turning colder” is how Rich Hoffman, News 12 Long Island meteorologist, summed up conditions for Thursday.

Gusty conditions continue through the overnight hours, said Brian Ciemnecki, weather service meteorologist based in Upton. Temperatures are also forecast to dip down overnight to the mid-20s.

Friday is still gusty, with the chance for afternoon snow showers or squalls — not widespread, but more hit-or-miss, Ciemnecki said. Only a quick coating to possible half-inch of snow is expected.

With Joan Gralla and Lisa Irizarry