This is the current conditions weather report for Holtsville. The report was made 59 minutes ago, at 02:56 UTC. The temperature was 68°F / 20°C, with a dew-point at 68°F / 20°C. The atmospheric pressure was 30 inHg / 1017 hPa. The relative humidity was 73%. The skies were clear.
Holtsville is a hamlet (and census-designated place) in Suffolk County, New York, United States. The population was 17,006 at the 2000 census.
Holtsville is the location of an IRS Processing Center (which has the lowest assigned numerical ZIP Code, 00501) and is in the Town of Brookhaven and the Town of Islip.
Holtsville is located at 40.813394, -73.047175.
According to the United States Census Bureau, the CDP has a total area of 18.0 km² (7.0 mi²), all land.
In the CDP the population was spread out with 28.2% under the age of 18, 7.5% from 18 to 24, 33.5% from 25 to 44, 23.9% from 45 to 64, and 6.9% who were 65 years of age or older. The median age was 34 years. For every 100 females there were 96.1 males. For every 100 females age 18 and over, there were 93.9 males.