Winter Weather — Southwest Suffolk, New York

2021-02-18 to 2021-02-19 · Southwest Suffolk, New York

Event narrative

The Official NWS Observation at the Islip Airport was 5.3 inches of snow. Trained spotters, NWS Employees, and the public reported 4 to 6 inches of snow. The Islip Airport ASOS recorded 0.17 inches of freezing rain.

Wider weather episode

A long duration wintry weather event occurred on Thursday, February 18, 2021 through Friday, February 19, 2021. A frontal wave of low pressure developed off the Middle Atlantic coast on February 18, 2021. The frontal wave combined with a strong upper level to produce a brief period of moderate to heavy snowfall during the morning and early afternoon on Thursday, February 18, 2021. The snow also mixed with sleet at times during the late morning and early afternoon hours across portions of the New York City metro and Long Island. Snowfall rates of 1 inch per hour occurred with locally 2 inches per hour at times. The precipitation became light and changed to spotty freezing rain and freezing drizzle during the late afternoon through the overnight hours on February 18, 2021. The overall weather pattern did not change to much on Friday, February 19, 2021. Weak waves of low pressure continued to track along the frontal zone off the Middle Atlantic coast, combining with the lingering strong jet stream aloft to produce periods of mainly light snow. The light snow persisted into the early evening hours before tapering off just before midnight on Friday, February 19, 2021.

Source: NOAA Storm Events Database, event_id 941857. Narrative written by the NWS forecast office that issued the report.